sl-model for paired comparisons
TRANSCRIPT
SL-Model for Paired Comparisons
By
Morné Rowan Sjölander
submitted in
fulfillment of the requirements
for the degree of
MSc
in the
Faculty of Science
at the
Nelson Mandela Metropolitan University
November 2006
Supervisor: Prof I.N. Litvine
2
Contents
0 Acknowledgements 6
1 Literature Review 7
2 Notation 13
3 The S and SS Distribution 13
4 Paired Comparisons S- and SS-Experisment 37
5 The SL-Model
5.1 The General SL-Model 47
5.2 The Binary SL-Model 48
5.3 The DDic01 Binary SL-Model 48
5.4 The DD01 Binary SL-Model 49
6 Results and Examples Illustrating Properties of the
SL-Model 50
6.1 Results of the Solution to the SL-Model
6.2 Examples illustrating further Properties of the SL-Model 55
3
7 Real Life Application
7.1 Data 71
7.2 Methodology 79
7.3 Real Life Application of the General SL-Model 80
7.4 Real Life Application of the Binary SL-Model 101
7.5 Real Life Application of the DDic01 Binary SL-Model 121
7.6 Real Life Application of the DD01 Binary SL-Model 141
7.7 Comparison to other models 161
7.7.1 General SL-Model vs Binary SL-Model 166
7.7.2 General SL-Model vs DDic01 Binary SL-Model 170
7.7.3 General SL-Model vs DD01 Binary SL-Model 174
7.7.4 General SL-Model vs Binomial Poisson Model (Bayesian Solution) 178
7.7.5 General SL-Model vs Binomial Poisson Model (Max. Like. Solution) 182
7.7.6 General SL-Model vs Bradley-Terry Model 186
7.7.7 General SL-Model vs Poisson Model 190
7.7.8 General SL-Model vs Approx. Algorithm of Bayesian Solution Poisson
Model 194
7.7.9 General SL-Model vs Row Sum Method 198
7.7.10 Binary SL-Model vs DDic01 Binary SL-Model 202
7.7.11 Binary SL-Model vs DD01 Binary SL-Model 206
7.7.12 Binary SL-Model vs Binomial Poisson Model (Bayesian Solution) 210
7.7.13 Binary SL-Model vs Binomial Poisson Model (Max. Like. Solution) 214
7.7.14 Binary SL-Model vs Bradley-Terry Model 218
7.7.15 Binary SL-Model vs Poisson Model 222
7.7.16 Binary SL-Model vs Approx. Algorithm of Bayesian Solution Poisson
Model 226
7.7.17 Binary SL-Model vs Row Sum Method 230
7.7.18 DDic01 Binary SL-Model vs DD01 Binary SL-Model 234
7.7.19 DDic01 Binary SL-Model vs Binomial Poisson Model (Bayesian
Solution) 238
4
7.7.20 DDic01 Binary SL-Model vs Binomial Poisson Model (Max. Like.
Solution) 242
7.7.21 DDic01 Binary SL-Model vs Bradley-Terry Model 246
7.7.22 DDic01 Binary SL-Model vs Poisson Model 250
7.7.23 DDic01 Binary SL-Model vs Approx. Algorithm of Bayesian Solution
Poisson Model 254
7.7.24 DDic01 Binary SL-Model vs Row Sum Method 258
7.7.25 DD01 Binary SL-Model vs Binomial Poisson Model (Bayesian Solution) 262
7.7.26 DD01 Binary SL-Model vs Binomial Poisson Model (Max. Like.
Solution) 266
7.7.27 DD01 Binary SL-Model vs Bradley-Terry Model 270
7.7.28 DD01 Binary SL-Model vs Poisson Model 274
7.7.29 DD01 Binary SL-Model vs Approx. Algorithm of Bayesian Solution
Poisson Model 278
7.7.30 DD01 Binary SL-Model vs Row Sum Method 282
7.7.31 Binomial Poisson Model (Bayesian Solution) vs Binomial Poisson Model
(Max. Like. Solution) 286
7.7.32 Binomial Poisson Model (Bayesian Solution) vs Bradley-Terry Model 290
7.7.33 Binomial Poisson Model (Bayesian Solution) vs Poisson Model 294
7.7.34 Binomial Poisson Model (Bayesian Solution) vs Approx. Algorithm of
Bayesian Solution Poisson Model 298
7.7.35 Binomial Poisson Model (Bayesian Solution) vs Row Sum Method 302
7.7.36 Binomial Poisson Model (Max. Like. Solution) vs Bradley-Terry Model 306
7.7.37 Binomial Poisson Model (Max. Like. Solution) vs Poisson Model 310
7.7.38 Binomial Poisson Model (Max. Like. Solution) vs Approx. Algorithm of
Bayesian Solution Poisson Model 314
7.7.39 Binomial Poisson Model (Max. Like. Solution) vs Row Sum Method 318
7.7.40 Bradley-Terry Model vs Poisson Model 322
7.7.41 Bradley-Terry Model vs Approx. Algorithm of Bayesian Solution Poisson
Model 326
7.7.42 Bradley-Terry Model vs Row Sum Method 330
5
7.7.43 Poisson Model vs Approx. Algorithm of Bayesian Solution Poisson
Model 324
7.7.44 Poisson Model vs Row Sum Method 338
7.7.45 Approx. Algorithm of Bayesian Solution Poisson Model vs Row Sum
Method 342
7.7.46 Summary 346
8 Conclusion 349
9 References 350
6
0 Acknowledgements
I would like to thank the following for their support, guidance and encouragement.
1. To my God, who has blessed me in so many aspects of my life, the most precious of all
being, that I can know Him as my Friend.
2. Prof. Litvine, for suggesting the topic of the study, for his encouraging words, his
support and motivation, and all his assistance.
3. To my family, for their unconditional love, encouragement, prayers and everything
they mean to me.
4. All my friends, also my friends from NMMU including students and lecturers, for
there friendships and encouragement.
7
1 Literature Review
The method of paired comparisons can be found all the way back to 1860, where Fechner
made the first publication in this method, using it for his psychometric investigations [4].
Thurstone formalised the method by providing a mathematical background to it [9-11]
and in 1927 the method’s birth took place with his psychometric publications, one being
“a law of comparative judgment” [12-14].
The law of comparative judgment is a set of equations relating the proportion of times
any stimulus k is judged greater on a given attribute than any other stimulus j to the
scales and discriminal dispersions of the two stimuli on the psychological continuum.
The set of equations is derived from the following postulates:
1. Each stimulus when presented to the observer (judge) gives rise to a discrimininal
process which has some value on the psychological continuum of interest.
2. Because of momentary fluctuations in the organism, a given stimulus does not always
excite the same discriminal process, but may excite one with a lower or higher value in
the continuum. If any stimulus is presented to an observer a large number of times, a
frequency distribution of discriminal processes associated with that stimulus will be
generated. It is postulated that the values of the discriminal process are such that the
frequency distribution is normal on the psychological continuum. Each stimulus thus has
associated with it a normal distribution of dicriminal processes.
3. The mean and standard deviation associated with a stimulus is taken as its scale value
and discriminal dispersion respectively [12, 2].
8
“The principals of the Thurstone-Mosteller model may be found in [8]:
1. There is a set of stimuli that can be located on a subjective continuum.
2. Each stimulus when presented to an individual gives rise to a sensation in the
individual.
3. The distribution of sensations from a particular stimulus for a population of individuals
is normal.
4. Stimuli are presented in pairs to an individual, thus giving rise to a sensation for each
stimulus. The individual compares these sensations and reports which is greater.
5. It is possible for these paired sensations to be correlated.
6. The task is to space the stimuli (the sensation means), except for a linear
transformation.”[7].
The method of paired comparisons is a generalization of the two-category case of the
method of constant stimuli. In the method of constant stimuli, each stimulus is compared
with a single standard, whilst in paired comparisons each stimulus (object) serves in turn
as a standard. Thus with n stimuli (objects) there are 2
)1n(n −pairs of objects [2].
Paired comparisons is seen as a technique used to rank objects (or stimuli) with respect to
a certain property which may not be seen as measurable in the usual sense or have a
formal definition but can only be judged subjectively e.g. ranking the attractiveness of
models, taste of wine, social preferences, colour comparisons, choice behavior etc. Paired
comparisons is thus widely used be psychometricians. People known as judges are
presented with pairs of objects, and for each pair of object they assign a preference or a
score which can say object 1 is better or worse than object 2, or object 1 is 3 times better
9
than object 2, or object 1 scores 5 while object 2 scores 6 etc. all depending on which
model of paired comparisons is used and the nature of the objects in the experiment. This
data is then inputted to the model, and then numbers known as weights are received for
each object. These numbers are then used to rank the objects i.e. the object with the
highest weight is ranked first, the object with the second highest weight is ranked second
etc. [4, 7].
The reason why objects are compared two at a time is because this avoids what is known
as sensory fatigue, which is the lack of concentration and the confusion believed to be
experienced by a person if he/she has to evaluate more than two objects at a time. Paired
comparisons is however also used in many other applications where objects are to be
compared in pairs for other reasons e.g. in sport statistics, the way lots of games work is
that teams or players play against each other two at a time, and then a score is obtained
from each game. Various other applications e.g. economic, military etc. of the method of
paired comparisons are also present [7].
Some of the main models for paired comparisons are the following:
Thurstone-Mosteller Model
Linear Model
Bradley-Terry Model
Regression Model
Poisson Model
Poisson Model (Approximate Algorithm of Bayesian Solution)
Binomial-Poisson Model (Bayesian Solution)
10
Binomial-Poisson Model (Maximum Likelihood Solution)
Row Sum Method and Generalised Row Sum Method
Analytical Hierarchy Process (AHP)
Haines-Litvine Model (Exponential AHP)
The last one and first four of the above models are continuous models for paired
comparisons; the next four are examples of discrete models, while the remaining two are
distribution-free models/method [7].
At first there were only continuous models for paired comparisons - discrete models are
quite new. Litvine and Hilliard-Lomas were the first to introduce models for discrete
populations in 1996 some being the poisson model, the poisson model (approximate
algorithm of bayesian solution), the binomial-poisson model (bayesian solution) and the
binomial-poisson model (maximum likelihood solution) [6, 7].
Before 1996, paired comparisons models for discrete distributions had not been
successfully constructed. Continuous models were used on discrete data, in which case
many assumptions that should have been met for using such models have been violated.
These violations were simply overlooked [5].
If score is discrete in nature, but is quite high generally then we can use continuous
models by approximating the score with continuous random variables. Examples of this
are in sports like rugby or basketball. However, if score is discrete and quite small like in
sports like soccer, tennis or hockey, using continuous approximations is not good.
In the models for paired comparisons, an underlying distribution of the scores is assumed,
except for the distribution-free models/methods in which no underlying distribution is
assumed. Obviously, a continuous model assumes a continuous underlying distribution
11
and a discrete model assumes a discrete underlying distribution hence the classification of
the model.
The Thurstone-Mosteller model assumes a normal distribution whilst the Bradley-Terry
model assumes quite a wide class of distributions, one of the most important being the
exponential distribution. The Haines-Litvine Model assumes an exponential underlying
distribution but utilizes ratios of underlying random variables [7].
The poisson model and the poisson model using an approximate algorithm of bayesian
solution assumes the underlying distribution of the scores is the Poisson distribution,
while the binomial-poisson model (bayesian solution) and the binomial-poisson model
(maximum likelihood solution) was developed in the sports context (football) as follows:
Xi|ni ~ Binomial(ni, pj)
Xj|nj ~ Binomial(nj, pi)
Where Xi and Xj are the number of goals scored in a match between team i and team j,
and ni and nj are the number of situations when the respective team had a real possibility
to score a goal and are distributed as follows:
ni ~ Poisson(λi)
nj ~ Poisson(λj)
It can be shown that:
Xi ~ Poisson(λipj)
Xj ~ Poisson(λjpi)
12
hence the name binomial-poisson model. [7]
The amount of research done for discrete models of paired comparisons is not a lot. This
study develops a new discrete model, the SL-model for paired comparisons. Paired
comparisons data processing in which objects have an upper limit to their scores was also
not yet developed, and making such a model is one of the aims of this report. The SL-
model is thus developed in this context; however, the model easily generalises to not
necessarily having an upper limit on scores.
A new distribution, the S-distribution, for the difference of pairs of scores is formulated
for the above situation where scores have upper limits. The underlying distribution of the
scores follows a truncated Negative Binomial distribution. We apply our model to real
life tennis data, and compare these results to the official rankings, and also to rankings
obtained using some of the other paired comparisons models mentioned in this section.
There are numerous other applications for our model, for example, economic and military
applications, as well as many other practical applications. Our model can also be used to
predict future scores, and small examples of this are given in section 6.
13
2 Notation
1. The function
<
≥=
+0 x if0
0 x ifx
2
|x|xwill be denoted x
*.
2. The function
<
≥=
−0 x ifx
0 x if0
2
|x|xwill be denoted
*x.
3. The function
<
≥=+
0 x ifb
0 x ifa
x
xb
x
xa
**
will be denoted w(x, a, b).
4. Evidently, w(x – c, a, b)
<
≥=
c x ifb
c x ifa
≥
<=
c x ifa
c x ifb.
5. If random variable Y ~ NB(r, p) and X = W(Y – s, s, Y)
≥
<=
s Y ifs
s Y ifY, then we
denote this as X ~ TNB(r, p, s).
6. Evidently, if X ~ TNB(r, p, s) then:
i) for x = 1, 2, …, s – 1, FX(x) =∑=
−
−+x
0j
jr )p1(pj
1jr
ii) FX(s) = 1
3 The S- and SS-Distributions
Definition 1: The S-Experiment
1. Suppose we have a series of Bernoulli trials.
2. Each trial results in either a success or a failure.
14
3. The probability of a success on any trial is p, and remains the same from trial to
trial. The probability of a failure thus remains 1 – p for each trial.
4. The trials are independent.
5. The experiment carries on until the rth success or the s
th failure, whichever occurs
first.
6. The random variable of interest is X, the number of successes minus the number
of failures.
Definition 2: The S-Distribution
If the random variable X denotes the number of successes minus the number of failures in
an S-experiment, we say that X follows the S-distribution, denoted X ~ S(r, s, p).
Definition 3: The SS-Distribution
If the random variable X ~ S(r, r, p) (i.e. X ~ S(r, s, p) where r = s), then X is said to
follow a SS-distribution, denoted X ~ SS(r, p).
Definition 4: The SS-Experiment
The S-experiment with r = s will be known as the SS-experiment.
Theorem 1:
If X ~ S(r, s, p) then the probability density function of X is given by:
p(x)
+−+−=−
−
−−
−+−+−−=−
−
−+
=−
+
r,...,2sr,1srxfor )p1(p1r
1xr2
1rs,...,1s,sfor x)p1(p1s
1xs2
xrr
sxs
r,...,2sr,1sr,1sr,...,1s,sfor x )p1(p1)s,r,srx(w
)1xr2,1xs2,srx(w)xr,smin()r,xsmin( +−+−−−+−−=−
−+−
−−−++−= −+
Proof:
Let X ~ S(r, s, p).
If experiment results in r successes:
x = r – s + 1, r – s + 2, …, r. We have 2r – x repeated Bernoulli trials.
15
For the event [getting r successes and b failures] i.e. [X = x where x = r – b], one must
obtain the rth success on the (2r – x)
th trial, by obtaining the event E1 that r – 1 successes
occur in the first 2r – x – 1 trials, in any order, and then the event E2 that a success is
obtained on the (2r – x)th trial.
Clearly, P(E1) = )1r()1xr2(1r )p1(p
1r
1xr2 −−−−− −
−
−−= xr1r )p1(p
1r
1xr2 −− −
−
−− and P(E2) = p.
Thus for x = r – s + 1, r – s + 2, …, r, we have that:
P(X = x) = P(E1)P(E2) = xrrxr1r )p1(p
1r
1xr2p)p1(p
1r
1xr2 −−− −
−
−−=×−
−
−−
If experiment results in s failures:
x = –s, –s + 1, …, –s + r – 1. We have 2s + x repeated Bernoulli trials.
For the event [getting b successes and s failures] i.e. [X = x where x = b – s], one must
obtain the sth failure on the (2s + x)
th trial, by obtaining the event E3 that s – 1 failure
occur in the first 2s + x – 1 trials, in any order, and then the event E4 that a failure is
obtained on the (2s + x)th trial.
Clearly, P(E3) =)1s()1xs2(1s p)p1(
1s
1xs2 −−−+−−
−
−+= xs1s p)p1(
1s
1xs2 +−−
−
−+,
and P(E4) = 1 – p.
Thus for x = –s, –s + 1, …, –s + r – 1, we have that:
P(X = x) = P(E1)P(E2) =
xssxs1s p)p1(1s
1xs2)p1(p)p1(
1s
1xs2 ++− −
−
−+=−×−
−
−+
16
+−+−=−
−
−−
−+−+−−=−
−
−+
===−
+
r,...,2sr,1srxfor )p1(p1r
1xr2
1rs,...,1s,sfor x)p1(p1s
1xs2
)xX(P)x(p :Thusxrr
sxs
r,...,2sr,1sr,1sr,...,1s,sfor x
)p1(p1)s,r,srx(w
)1xr2,1xs2,srx(w)xr,smin()r,xsmin(
+−+−−−+−−=
−
−+−
−−−++−= −+
The joining using minimization is evident due to the values of x.
Corollary 1:
If X ~ SS(r, p) then the probability density function of X is given by:
r 1,-r 2,..., 1, 1, 2, ..., 1,r r,for x)p1(p1r
1|x|r2)x(p
**xrxr −−+−−=−
−
−−= −+
Proof:
If X ~ SS(r, p) then X ~ S(r, r, p), thus:
p(x)
=−
−
−−
−+−−=−
−
−+
=−
+
r,...,2,1xfor )p1(p1r
1xr2
1,...,1r,rfor x)p1(p1r
1xr2
xrr
rxr
r 1,-r 2,..., 1, 1, 2, ..., 1,r r,for x)p1(p1r
1|x|r2
r,...,2,1xfor )p1(p1r
1|x|r2
1,...,1r,rfor x)p1(p1r
1|x|r2
**
**
**
xrxr
xrxr
xrxr
−−+−−=−
−
−−=
=−
−
−−
−+−−=−
−
−−
=
−+
−+
−+
Graph of the probability density function of the S distribution:
We set r = s = 10 and plotted the graph of the probability density function of the SS
distribution for p = 0.1, 0.2, …, 0.9 using Mathematica:
17
f@x_D:= µ Binomial@2 s+x−1, s−1D∗p^Hr+xL∗H1− pL^s x∈ Integers&&x≥ −s&&x< r−sBinomial@2 r−x−1, r−1D∗p^r∗H1− pL^Hr−xL x∈ Integers&&x >r−s&&x≤ r
r=10
10
s=10
10
For[i=1,i<10,p=0.1i;Print["p = ",p];
values=Join[Table[{x,f[x]},{x,-s,r-s–1}],
Table[{x,f[x]},{x,r-s+1,r}]];
ListPlot[values,PlotStyle→PointSize[0.02]];i++]
p = 0.1
-10 -5 5 10
0.05
0.1
0.15
p = 0.2
-10 -5 5 10
0.05
0.1
0.15
0.2
18
p = 0.3
-10 -5 5 10
0.025
0.05
0.075
0.1
0.125
0.15
p = 0.4
-10 -5 5 10
0.02
0.04
0.06
0.08
0.1
0.12
p = 0.5
-10 -5 5 10
0.02
0.04
0.06
0.08
19
p = 0.6
-10 -5 5 10
0.02
0.04
0.06
0.08
0.1
0.12
p = 0.7
-10 -5 5 10
0.025
0.05
0.075
0.1
0.125
0.15
p = 0.8
-10 -5 5 10
0.05
0.1
0.15
0.2
20
p = 0.9
-10 -5 5 10
0.05
0.1
0.15
We note that for small values of p, the SS distribution is positively skewed, for p = 0.5, it
is symmetric, and for large values of p, it is negatively skewed.
Next we set r = 10 and p = 0.5 and plot the graph of the probability density function of
the S distribution for s = 0, 1, 2, …, 20 using Mathematica:
f@x_D:=
µ Binomial@2 s+x−1,s−1D∗p^Hr+xL∗H1− pL^s x∈ Integers&&x≥ −s&&x< r−sBinomial@2 r−x−1,r−1D∗p^r∗H1− pL^Hr−xL x∈ Integers&&x >r−s&&x≤ r
r=10
10
p=0.5
0.5
For[s=0,s≤20,Print["s = ",s];
values=Join[Table[{x,f[x]},{x,-s,r-s–1}],
Table[{x,f[x]},{x,r-s+1,r}]];
ListPlot[values,PlotStyle→PointSize[0.02]];s++]
21
s = 0
2 4 6 8
-1
-0.5
0.5
1
s = 1
2 4 6 8 10
0.0002
0.0004
0.0006
0.0008
0.001
s = 2
-2 2 4 6 8 10
0.0005
0.001
0.0015
0.002
22
s = 3
-2 2 4 6 8 10
0.0005
0.001
0.0015
0.002
0.0025
0.003
s = 4
-4 -2 2 4 6 8 10
0.002
0.004
0.006
0.008
0.01
s = 5
-4 -2 2 4 6 8 10
0.005
0.01
0.015
0.02
0.025
0.03
23
s = 6
-5 -2.5 2.5 5 7.5 10
0.01
0.02
0.03
0.04
0.05
0.06
s = 7
-5 -2.5 2.5 5 7.5 10
0.02
0.04
0.06
s = 8
-7.5 -5 -2.5 2.5 5 7.5 10
0.02
0.04
0.06
0.08
24
s = 9
-7.5 -5 -2.5 2.5 5 7.5 10
0.02
0.04
0.06
0.08
s = 10
-10 -5 5 10
0.02
0.04
0.06
0.08
s = 11
-10 -5 5 10
0.025
0.05
0.075
0.1
0.125
0.15
0.175
25
s = 12
-10 -5 5 10
0.05
0.1
0.15
0.2
0.25
0.3
s = 13
-10 -5 5 10
0.1
0.2
0.3
0.4
0.5
s = 14
-10 -5 5 10
0.1
0.2
0.3
0.4
0.5
0.6
26
s = 15
-15 -10 -5 5 10
0.2
0.4
0.6
0.8
s = 16
-15 -10 -5 5 10
0.2
0.4
0.6
0.8
1
s = 17
-15 -10 -5 5 10
0.25
0.5
0.75
1
1.25
1.5
27
s = 18
-15 -10 -5 5 10
0.5
1
1.5
2
s = 19
-15 -10 -5 5 10
0.2
0.4
0.6
0.8
1
s = 20
-20 -15 -10 -5 5 10
0.2
0.4
0.6
0.8
1
1.2
As can be seen from the graph, this yields an interesting pattern.
28
Example 1:
Suppose we have 2 sport teams, and the team that score 3 first wins. The probability that
team 1 scores in a round is 0.3. Thus X ~ SS(3, 0.3)/
Scores Calculations
x1 x2 x = x1 – x2
x1 + x2
= 2r – |X|
−
−−
1r
1|x|r2
xr *+ *xr − )x(p
0 3 –3 3 1 0 3 0.343
1 3 –2 4 3 1 3 0.3087
2 3 –1 5 6 2 3 0.18522
3 2 1 5 6 3 2 0.07938
3 1 2 4 3 3 1 0.0567
3 0 3 3 1 3 0 0.027
1
That is: p(x) = 3 2, 1, 1, 2, 3,for x7.03.013
1|x|6 **x3x3 −−−=
−
−− −+
=
=
=
−=
−=
−=
=
3x0.027
2x0.0567
1x0.07938
1x0.18522
2x0.3087
3x0.343
The probability density function was plotted with Mathematica:
f@x_D:= µ Binomial@2 s+x−1, s−1D∗p^Hr+xL∗H1− pL^s x∈ Integers&&x≥ −s&&x< r−sBinomial@2 r−x−1, r−1D∗p^r∗H1− pL^Hr−xL x∈ Integers&&x >r−s&&x≤ r
r=3
3
s=3
3
p=0.3
29
0.3
values=Join[Table[{x,f[x]},{x,-s,r-s–1}],Table[{x,f[x]},
{x,r-s+1,r}]]
{{-3,0.343},{-2,0.3087},{–1,0.18522},
{1,0.07938},{2,0.0567},{3,0.027}}
ListPlot[values,PlotStyle→PointSize[0.02]];
-3 -2 -1 1 2 3
0.05
0.15
0.2
0.25
0.3
0.35
Example 2:
Suppose we have a person in a helicopter and a person in a boat at war. If the helicopter
is shot 8 times, it falls. If the boat is shot 5 times, it sinks. When a shot is fired, the
probability that it is the person in the boat whose shot hits the helicopter is 0.4.
Thus p = P(boat shoots helicopter) = 0.4.
r = 8
s = 5
30
Thus X ~ S(8, 5, 0.4).
Scores Calculations
X1 X2 X = X1 – X2 combination min(s + x,r) min(s,r – x) p(x)
0 5 –5 1 0 5 0.03125
1 5 –4 5 1 5 0.078125
2 5 –3 15 2 5 0.117188
3 5 –2 35 3 5 0.136719
4 5 –1 70 4 5 0.136719
5 5 0 126 5 5 0.123047
6 5 1 210 6 5 0.102539
7 5 2 330 7 5 0.080566
8 4 4 330 8 4 0.080566
8 3 5 120 8 3 0.058594
8 2 6 36 8 2 0.035156
8 1 7 8 8 1 0.015625
8 0 8 1 8 0 0.003906
1
That is: p(x)
=−
−
−−=−
+
=−
+
8,...,5,4xfor )p1(p7
x15
2,...,4,5for x)p1(p4
x9
x88
5x5
which results in the probabilities as tabulated.
The probability density function was plotted with Mathematica:
f@x_D:= µ Binomial@2 s+x−1,s−1D∗p^Hr+xL∗H1− pL^s x∈ Integers&&x≥ −s&&x< r−sBinomial@2 r−x−1,r−1D∗p^r∗H1− pL^Hr−xL x∈ Integers&&x >r−s&&x≤ r
r=8
8
s=5
5
p=0.4
31
0.4
values=Join[Table[{x,f[x]},{x,-s,r-s–1}],Table[{x,f[x]},
{x,r-s+1,r}]]
{{-5,0.00497664},{-4,0.00995328},{-3,0.0119439},
{-2,0.0111477},{–1,0.00891814},{0,0.00642106},
{1,0.00428071},{2,0.00269073},{4,0.0280284},{5,0.0169869},
{6,0.00849347},{7,0.00314573},{8,0.00065536}}
ListPlot[values,PlotStyle→PointSize[0.02]];
-4 -2 2 4 6 8
0.005
0.01
0.015
0.02
0.025
Lemma 1:
If B(x; n, p) is the cumulative distribution function of Binomial(n, p) distribution at x
then:
)p,1sr;1r(B −+− = ( ) )p
1p,s1,r1,1(Fp1p
s
s1r12
s1r −+−−
+− −
Proof:
)p,1sr;1r(B −+− = 1 – )p1,1sr;1s(B −−+−
(by a result on P93 of Bain and Engelhardt [1])
32
= 1 –
+ΓΓ
−+−+Γ+−
−
−+
−+
)1s()r(
)p
1p,s1,r1,1(F)sr()
p
11(
p
1p
12
s1sr
1sr (by Mathematica)
( )
( ) ( ) )p
1p,s1,r1,1(Fp1p
s
s1r)
p
1p,s1,r1,1(Fp1p
!s)!1r(
)!1sr(
)p
1p,s1,r1,1(Fp1pp
)1s()r(
)sr(
)1s()r(
)p
1p,s1,r1,1(F)sr(
p
p1
p11
12
s1r
12
s1r
12
ss1sr
12
s
1sr
−+−−
+−=
−+−−
−
−+=
−+−−
+ΓΓ
+Γ=
+ΓΓ
−+−+Γ
−
−−=
−−
−−+
−+
Theorem 2:
If X ~ S(r, s, p), and B(x; n, p) is the cumulative distribution function of Binomial(n, p)
distribution at x, then:
i) The probability density function of X is a proper probability density function.
ii) P(Experiment ends due to r successes) = P(X > r – s) = )p1,1sr;1s(B −−+−
= ( ) )p1
p,r1,s1,1(Fpp1
r
r1s12
r1s
−−
+−−
+− −.
iii) P(Experiment ends due to s failures) = P(X < r – s) = )p,1sr;1r(B −+−
= ( ) )p
1p,s1,r1,1(Fp1p
s
s1r12
s1r −+−−
+− − .
Proof:
i) We first show that f(x) ≥ 0 for all x and then we showed that ∑ =x
1)x(f .
f(x)
+−+−=−
−
−−
−+−+−−=−
−
−+
=−
+
r,...,2sr,1srxfor )p1(p1r
1xr2
1rs,...,1s,sfor x)p1(p1s
1xs2
xrr
sxs
33
:1rs,...,1s,sFor x −+−+−−=
1xs2 −+ ≥ s – 1 ≥ 0 thus
−
−+
1s
1xs2exists and obviously
−
−+
1s
1xs2≥ 0.
xsp + and s)p1( − are obviously both positive by property of exponential function.
:r,...,2sr,1srxFor +−+−=
1xr2 −− ≥ r – 1 ≥ 0 thus
−
−−
1r
1xr2 exists and obviously
−
−−
1r
1xr2≥ 0.
rp and xr)p1( −− are obviously both positive by property of exponential function.
Thus f(x) ≥ 0 for all x.
∑∑
∑∑∑
+−=
−
+−=
−
+−=
−−+−
−=
+
−
−
−−+−
−
−−=
−
−
−−+−
−
−+=
r
1srx
xrrs
1rsx
sxs
r
1srx
xrr1rs
sx
sxs
x
)p1(p1r
1xr2)p1(p
1s
1xs2
)p1(p1r
1xr2)p1(p
1s
1xs2)x(f
Let y = s – x. Thus if x = s – r + 1, s – r + 2, …, s, then y = 0, 1,…, r – 1.
Let z = r – x. Thus if x = r – s + 1, r – s + 2, …, r, then z = 0, 1,…, s – 1.
∑∑∑−
=
−
=
−
−
−++−
−
−+=
1s
0z
zr1r
0y
sy
x
)p1(p1r
1zr)p1(p
1s
1ys)x(f
Let q = 1 – p, Y ~ NB(r, p), Y' ~ NB(s, q), W ~ Bin(s + r – 1, p), W' ~ Bin(s + r – 1, q).
A result on P103 of Bain and Engelhardt [1] says that:
If X ~ NB*(s, p) and W ~ Bin(n, p), then P(X ≤ n) = P(W ≥ s).
However, in this book the Negative Binomial Distribution’s X is our X + s.
If Y ~ NB(s, p) and W ~ Bin(n, p), then P(Y ≤ n – s) = P(W ≥ s).
If Y ~ NB(s, p) and W ~ Bin(s + r – 1, p), then P(Y < r) = P(Y ≤ r – 1) = P(W ≥ s).
Similarly for Y' and W'.
34
Thus:
)r'W(P)sW(P)s'Y(P)rY(P)x(fx
≥+≥=<+<=∑
A result on P93 of Bain and Engelhardt [1] implies that:
P(W ≤ w) = 1 – P(W' ≤ s + r – 1 – w – 1) = 1 – P(W' ≤ s + r – w – 2)
So:
P(W ≥ s) = 1 – P(W < s) = 1 – P(W ≤ s – 1) = P(W' ≤ s + r – (s – 1) – 2) = P(W' ≤ r – 1)
1)r'W(P)r'W(P1)r'W(P)1r'W(P)x(fx
=≥+≥−=≥+−≤=∑
ii) As X = number of successes minus number of failures, we have that:
P(Experiment ends due to r successes) = P(X > r – s)
∑∑+−=
−
−>
−
−
−−==
r
1srx
xrr
srx
)p1(p1r
1xr2)x(f
Let y = r – x. Thus if x = r – s + 1, r – s + 2, …, r, then y = 0, 1, …, s – 1.
P(Experiment ends due to r successes) ∑∑−
=
−
=
−
−+=−
−
−+=
1s
0y
yr1s
0y
yr )p1(py
1yr)p1(p
1r
1yr
Let Y ~ NB(r, p) and W ~ Bin(r + s – 1, p).
A result on P103 of Bain and Engelhardt [1] says that:
If X ~ NB*(r, p) and W ~ Bin(n, p), then P(X ≤ n) = P(W ≥ r).
However, in this book the Negative Binomial Distribution’s X is our X + r.
If Y ~ NB(r, p) and W ~ Bin(n, p), then P(Y ≤ n – r) = P(W ≥ r).
If Y ~ NB(r, p) and W ~ Bin(r + s – 1, p), then P(Y ≤ s – 1) = P(W ≥ r).
P(Experiment ends due to r successes)
)p,1sr;1r(B1)1rW(P1)rW(P)sY(P −+−−=−≤−=≥=≤= = )p1,1sr;1s(B −−+−
(by a result on P93 of Bain and Engelhardt [1])
35
= ( ) )p1
p,r1,s1,1(Fpp1
r
r1s12
r1s
−−
+−−
+− −(By Lemma 1)
iii) P(Experiment ends due to s failures) = P(X < r – s)
= 1 – P(X ≥ r – s) = 1 – P(X > r – s)
= 1 – P(Experiment ends due to r successes) = 1 – [ )p,1sr;1r(B1 −+−− ]
= )p,1sr;1r(B −+− = ( ) )p
1p,s1,r1,1(Fp1p
s
s1r12
s1r −+−−
+− − (by Lemma 1)
Corollary 2:
If X ~ SS(r, p), and B(x; n, p) is cumulative distribution function of Binomial(n, p)
distribution at x, then:
i) The probability density function of X is a proper probability density function.
ii) P(Experiment ends due to r successes) = P(X > 0) =
( ) )p1
p,r1,r1,1(Fpp1
r
1r212
r1r
−
−+−−
− −.
iii) P(Experiment ends due to r failures) = P(X < 0) =
( ) )p
1p,r1,r1,1(Fp1p
r
1r212
r1r −+−−
− − .
Proof: Evident from Theorem 2 as, if X ~ SS(r, p) then X ~ S(r, r, p).
Theorem 3:
If X = X1 – X2 where X1 ~ TNB(s, 1 – p, r) and X2 ~ TNB(r, p, s), then X ~ S(r, s, p).
Proof:
X = –s, –s + 1, …, –s + r – 1 corresponds to X1 = 0, 1, 2, …, r – 1 and X2 = s.
Thus for x = –s, –s + 1, …, –s + r – 1:
=≤= )xX(P)x(FX P(X1 – X2 ≤ x) = P(X1 – s ≤ x) = P(X1 ≤ x + s) =
∑∑+
=
+
=
−
−
−+=−−−
−+ sx
0j
sjsx
0j
js )p1(p1s
1js))p1(1()p1(
j
1js
36
Let i = j – s. Thus j = i + s. Thus =)x(FX ∑−=
+ −
−
−+x
si
sis )p1(p1s
1is2, which is the
cumulative distribution function of the S(r, s, p) distribution for x = –s, –s + 1, …,
–s + r – 1.
X = r – s + 1, r – s + 2, …, r corresponds to X1 = r and X2 = 0, 1, 2, …, r – 1.
Thus for x = r – s + 1, r – s + 2, …, r:
=≤= )xX(P)x(FX P(X1 – X2 ≤ x) = P(r – X2 ≤ x) = P(X2 ≥ r – x) = 1 – P(X2 ≤ r – x – 1)
= 1 – ∑=
−
−+x
0j
jr )p1(pj
1jr= 1 – ∑
−−
=
−
−
−+1xr
0j
jr )p1(p1r
1jr
Let i = r – j. Thus j = r – i. Thus =)x(FX 1 – ∑+=
−−
−
−−r
1xi
irr )p1(p1r
1ir2
∑∑∑+=
−
++=
−−+−
−=
+ −
−
−−−−
−
−−+−
−
−+=
r
1xi
irrr
1sri
xrr1rs
si
sxs )p1(p1r
1ir2)p1(p
1r
1xr2)p1(p
1s
1xs2
∑∑++=
−−+−
−=
+ −
−
−−+−
−
−+=
x
1sri
xrr1rs
si
sxs )p1(p1r
1xr2)p1(p
1s
1xs2,
which is the cumulative distribution function of the S(r, s, p) distribution for x = r – s + 1,
r – s + 2, …, r.
Thus X ~ S(r, s, p).
Corollary 3:
If X = X1 – X2 where X1 ~ TNB(r, 1 – p, r) and X2 ~ TNB(r, p, r), then X ~ SS(r, p).
Proof: Evident from Theorem 3 as if X ~ SS(r, p) then X ~ S(r, r, p).
Note 1:
The converse of Theorem 3 and Corollary 3 holds if X1 is the number of successes and
X2 is the number of failures where X is the number of successes minus the number of
failures. This holds similarly for Corollary 4 and 5.
37
4 Paired Comparisons S and SS-Experiment
Definition 5: The Paired Comparisons S-Experiment with t objects
1. Suppose we have t objects, A1, A2, …, At.
2. Each object gets compared (completes) against each other object dij times with S-
experiments.
3. For the random variables Xij ~ S(rij, rji, pij) for i, j = 1, 2, …, t, a success is if
object i scores a point when competing with object j, and a failure is if object j
scores an point when competing with object i.
4. The probability of a success on any trial is pij during all comparisons wherein Ai
competes with Aj, and remains the same from trial to trial in such comparisons.
The probability of a failure thus remains 1 – pij = pji for each trial.
5. The experiment carries on until the rijth success or the rji
th failure, whichever
occurs first.
6. The random variable of interest is Xij, the number of successes minus the number
of failures i.e. Xij = Xi|j – Xj|i where Xi|j is Ai’s score when competing against Aj
and Xj|i is Aj’s score when competing against Ai.
Special cases:
1. rij = ri for all j.
2. rij = rj for all i.
3. rij = r for all i, j as in Corollary 5.
4. dij = d for all i, j
Special case 1 is where the upper limit on the score that an object can get, depends on the
object scoring, for example, if we have 3 sportsmen playing a certain sport against each
other, and the A1 is 10 years old, A2 is 16 years old, and A3 is 20 years old, we may say
the games carry on until the first person scores half his age, to make the games more fair,
so for example when A2 is competing against A3, the game carries on until A2 scores 8
points, or A3 scores ten points, which ever occurs first.
38
Special case 2 is where the upper limit on the score that an object can get, depends on the
object being scored against. For example, if we have tanks at war, the number of times an
object (a tank) must be shot to be destroyed depends not on whose shooting, but on how
strong the tank is that is being shot at.
Special case 3 is where the upper limit on the scores is the same for all comparisons, e.g.
in a certain sport, all games may continue until a player scores 6 points.
Definition 6: Balanced Paired Comparisons S-Experiment with t objects
This is special case 4 of the Paired Comparisons S-experiment with t objects.
Definition 7: Paired Comparisons SS-Experiment with t objects
This is special case 3 of the Paired Comparisons S-experiment with t objects
i.e. Xij ~ SS(r, pij) (as SS(r, pij) is the same as S(r, r, pij).)
Definition 8: The Balanced Paired Comparisons SS-Experiment with t objects
This is special case 3 of the Balanced Paired Comparisons S-experiment with t objects
i.e. Xij ~ SS(r, pij) (as SS(r, pij) is the same as S(r, r, pij).)
Corollary 4:
If Xij = Xi|j – Xj|i where Xi|j ~ TNB(rji, pji, rij) and Xj|i ~ TNB(rij, pij, rji), then
Xij ~ S(rij, rji, pij), and Xji = Xj|i – Xi|j = – Xij ~ S(rji, rij, pji), where pij = 1 – pji.
Proof: Evident from Theorem 3 and evident in general.
Corollary 5:
If Xij = Xi|j – Xj|i where Xi|j ~ TNB(r, pji, r) and Xj|i ~ TNB(r, pij, r), then Xij ~ SS(r, pij),
and Xji = Xj|i – Xi|j = –Xij ~ S(r, pji), where pij = 1 – pji.
Proof: Evident from Corollary 4 as if X ~ SS(r, p) then X ~ S(r, r, p).
39
5 The SL-Model
Theorem 4:
Define values pi for i = 1, 2, …, t such that pij = 2
pp
2
1
2
p1p jiji −+=
−+. Then:
i) pji = 1 – pij ii) 2
1ppp jkijik −+=
iii) pij ≥ 0 iv) pij ≤ 1
v) If pi increases then pij increases, and if pj increases then pij decreases.
vi) ji pp > if and only if 2
1pij > . vii) If
2
1p,p jkij ≥ then
2
1p ik > .
Proof:
i) 1 – pij = ji
ijjijip
2
pp
2
1
2
pp
2
1
2
pp
2
11 =
−+=
−−=
−+−
ii) ikkikjji
jkij p2
pp
2
1
2
1
2
pp
2
1
2
pp
2
1
2
1pp =
−+=−
−++
−+=−+
iii) pij 02
1
2
1
2
10
2
1
2
pp
2
1 ji =−=−
+≥−
+=
iv) pij = 12
1
2
1
2
01
2
1
2
pp
2
1 ji =+=−
+≤−
+
v) Evident.
vi) 2
1p
2
1
2
pp
2
10
2
pp0pppp ij
jiji
jiji >⇔>−
+⇔>−
⇔>−⇔>
vii) 2
1p,p jkij ≥ . Thus 1pp jkij ≥+ . Thus
2
1ppp jkijik −+=
2
1≥ (using ii).
From the above properties of pij defined as pij = 2
pp
2
1
2
p1p jiji −+=
−+, we conclude
that pij is well defined.
40
Theorem 5:
Suppose we have the Balanced Paired Comparisons S-experiment with t objects, and that
2
pp
2
1
2
p1pp
jiji
ij
−+=
−+= , then the MLE’s of the pi’s can be found by solving the
following t equations: ∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t,
for the t unknowns ip̂ for i = 1, 2, …, t, where ∑=
=d
1c
)c(
j|ij|i xx and )c(
ijx is value that Xij
takes on in round c for c = 1, 2, …, d, and where
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx . ( )c(
j|ix is
Ai’s score when competing against Aj in round c.)
Proof:
Let Xij be Ai’s score when playing against Aj minus Aj’s score when playing against Ai.
Xij takes on the value)c(
ijx on observation number c i.e. )c(
ijx is Ai’s score when playing
against Aj in round c minus Aj’s score when playing against Ai in round c.
Evidently, )c(
ijx = – )c(
jix and pij = 1 – pji. Thus:
+−=
−+
−+
−
−−
−+−−=
−+
−+
−
−+
=−
+
ijjiij
)c(
ij
x r
ij
r
ji
ij
)c(
ijij
ijjiji
)c(
ij
r
ij
x r
ji
ji
)c(
ijji
)c(
ijij
r,...,1rrxfor 2
p1p
2
p1p
1r
1x r2
1rr,...,rxfor 2
p1p
2
p1p
1r
1x r2
)x (f
)c(ijijij
ji)c(
ijji
+−=
−+
−+
−
−+
+−=
−+
−+
−
−+
=+
+
ijjiij
)c(
ij
x r
ij
r
ji
ij
)c(
jiij
jiiji
)c(
ji
x r
ij
r
ji
ji
)c(
ijji
r,...,1rrxfor 2
p1p
2
p1p
1r
1x r2
r,...,1rrxfor 2
p1p
2
p1p
1r
1x r2
)c(jiijij
)c(ijjiji
Clearly )x (f)x (f )c(
jiji
)c(
ijij = . If )c(
ijx > rij – rji then clearly)c(
jix < rji – rij.
41
It is thus evident that { )x (f )c(
ijij : i < j} = { )x (f )c(
ijij : )c(
ijx > rij – rji}.
∏ ∏
∏ ∏∏∏
= −>
−
= −>= <
−+
−+=
==
d
1c rrx
xr
ij
r
ji
d
1c rrx
)c(
ijij
d
1c ji
)c(
ijijt1
jiij)c(
ij
)c(ijijij
jiij)c(
ij
2
p1p
2
p1pC
)x(f)x(f)p,...,p(L
Constant C =
−
−+
1r
1x r2
j
)c(
ijji.
Let
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx .
Thus
−>−
−<=
−<+
−>=
jiij
)c(
ij
)c(
ijij
jiij
)c(
ijji
ijji
)c(
ji
)c(
jiij
ijji
)c(
jiji)c(
i|jrr xifxr
rr xifr
rr xifxr
rr xifrx
∏∏∏ ∏
∏ ∏
∏ ∏
= == −>
= −>
= −>
−
−+=
−+
−+=
−+
−+=
−+
−+=
d
1c
t
1j,i
x
jid
1c rrx:j,i
x
ij
x
ji
1
d
1c rrx:j,i
x
ij
x
ji
d
1c rrx
xr
ij
r
ji
t1
)c(j|i
jiijij
)c(i|j
)c(j|i
jiijij
)c(i|j
)c(j|i
jiij)c(
ij
)c(ijijij
2
p1p
2
p1p
2
p1pC
2
p1p
2
p1pC
2
p1p
2
p1pC)p,...,p(L
We define c,i 0x )c(
i|i ∀= . Constant ∏ ∏= −>
=d
1c rrx:j,i
x
1
jiijij
)c(i|jCC .
∑∑∑ ∑
∑∑∑∑
=== =
= == =
−++=
−++=
−++=
−++=
−++=
t
1j,i
ji
j|i2
t
1j,i
j|i
ji
2
t
1j,i
d
1c
)c(
j|i
ji
2
t
1j,i
d
1c
ji)c(
j|i2
d
1c
t
1j,i
ji)c(
j|i2t1
2
p1plnxCx
2
p1plnCx
2
p1plnC
2
p1plnxC
2
p1plnxC)p,...,p(l
Constant )Cln(C 12 = .
∑∑∑∑
∑∑
====
==
−++
−+
−=
−+
+
−−+
=
−+
∂∂
+
−+
∂∂
=∂∂
t
1j jk
j|kt
1j kj
k|jt
1j jk
j|kt
1i ki
k|i
t
1j
jk
j|k
k
t
1i
ki
k|i
kk
p1p
x
p1p
x
2
1
p1p
x2
2
1
p1p
x2
2
p1plnx
p2
p1plnx
pp
l
42
Thus the MLE’s of the pi’s, i.e. the ip̂ ’s, are found by solving the following t equations:
∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t,
for the t unknowns ip̂ for i = 1, 2, …, t, where ∑=
=d
1c
)c(
j|ij|i xx and )c(
ijx is value that Xij takes
on in round c for c = 1, 2, …, d and where
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx . (xi|j is Ai’s
score when competing against Aj in round c.)
Corollary 5:
Suppose we have the Balanced Paired Comparisons S-experiment with t objects, d=1,
and that2
pp
2
1
2
p1pp
jiji
ij
−+=
−+= , then the MLE’s of the pi’s can be found by
solving the following t equations: ∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t,
for the t unknowns ip̂ for i = 1, 2, …, t, where
−<+
−>=
jiijijijji
jiijijij
j|i rr xifxr
rr xifrx . ( )c(
j|ix is Ai’s
score when competing against Aj.)
Proof:
Evident from Theorem 5.
Theorem 6:
Suppose we have the Paired Comparisons S-experiment with t objects, and that
2
pp
2
1
2
p1pp
jiji
ij
−+=
−+= , then the MLE’s of the pi’s can be found by solving the
following t equations: ∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t,
43
for the t unknowns ip̂ for i = 1, 2, …, t, where ∑=
=ijd
1c
)c(
j|ij|i xx and )c(
ijx is value that Xij takes
on in round c for c = 1, 2, …, dij and where
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx . ( )c(
j|ix is Ai’s
score when competing against Aj in round c.)
Proof:
Let Xij be Ai’s score when playing against Aj minus Aj’s score when playing against Ai.
Xij takes on the value)c(
ijx on observation number c i.e. )c(
ijx is Ai’s score when playing
against Aj in round c minus Aj’s score when playing against Ai in round c.
Evidently, )c(
ijx = – )c(
jix and pij = 1 – pji. Thus:
+−=
−+
−+
−
−−
−+−−=
−+
−+
−
−+
=−
+
ijjiij
)c(
ij
x r
ij
r
ji
ij
)c(
ijij
ijjiji
)c(
ij
r
ij
x r
ji
ji
)c(
ijji
)c(
ijij
r,...,1rrxfor 2
p1p
2
p1p
1r
1x r2
1rr,...,rxfor 2
p1p
2
p1p
1r
1x r2
)x (f
)c(ijijij
ji)c(
ijji
Let
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx .
Thus
−>−
−<=
−<+
−>=
jiij
)c(
ij
)c(
ijij
jiij
)c(
ijji
ijji
)c(
ji
)c(
jiij
ijji
)c(
jiji)c(
i|jrr xifxr
rr xifr
rr xifxr
rr xifrx .
Thus 1rr,...,rxfor ijjiji
)c(
ij −+−−= , we have that )c(
j|i
)c(
ijji xxr =+ , )c(
i|jji xr = , and
−
−+=
−
−++=
−
−+
1x
1xx
1r
1x rr
1r
1x r2)c(
i|j
)c(
j|i
)c(
i|j
ji
)c(
ijjiji
ji
)c(
ijji
.
And ijjiij
)c(
ij r,...,1rrxfor +−= , we have that )c(
j|iij xr = , )c(
i|j
)c(
ijij xxr =− and
−
−+=
−
−−+=
−
−−
1x
1xx
1r
1x rr
1r
1x r2)c(
j|i
)c(
i|j
)c(
j|i
ij
)c(
ijijij
ij
)c(
ijij.
44
∏∏∏∏
∏∏∏∏
∏∏∏∏
∏∏∏∏
= =≠ =
< =< =
< =< =
< =< =
−+=
−+=
−+
−+=
−+
−+=
−+
−+==
+−=
−+
−+
−
−+
−+−−=
−+
−+
−
−+
=
t
1j,i
d
1c
x
ji
1
ji
d
1c
x
ji
1
ij
d
1c
x
ji
ji
d
1c
x
ji
1
ji
d
1c
x
ij
ji
d
1c
x
ji
1
ji
d
1c
x
ij
x
ji)c(
ij
ji
d
1c
)c(
ijijt1
ijjiij
)c(
ij
x
ij
x
ji
)c(
j|i
)c(
i|j
)c(
j|i
ijjiji
)c(
ij
x
ij
x
ji
)c(
i|j
)c(
j|i
)c(
i|j
)c(
ijij
ij
)c(j|iij
)c(j|i
ij
)c(j|iij
)c(j|i
ij
)c(i|jij
)c(j|i
ij
)c(i|j
)c(j|iij
)c(i|j
)c(j|i
)c(i|j
)c(j|i
2
p1pC
2
p1pC
2
p1p
2
p1pC
2
p1p
2
p1pC
2
p1p
2
p1pC)x(f)p,...,p(L
r,...,1rrxfor 2
p1p
2
p1p
1x
1xx
1rr,...,rxfor 2
p1p
2
p1p
1x
1xx
)x (f
We define c,i 0x )c(
i|i ∀= . Constant
−>
−
−+
−<
−
−+
=
jiij
)c(
ij)c(
j|i
)c(
i|j
)c(
j|i
jiij
)c(
ij)c(
i|j
)c(
j|i
)c(
i|j
)c(
ij
rrx if1x
1xx
rrx if1x
1xx
C and
constant ∏∏< =
=ji
d
1c
)c(
ij1
ij
CC . (Constants are constant with respect to pk’s.)
∑∑∑ ∑
∑∑
=== =
= =
−++=
−++=
−++=
−++=
t
1j,i
ji
j|i2
t
1j,i
j|i
ji
2
t
1j,i
d
1c
)c(
j|i
ji
2
t
1j,i
d
1c
ji)c(
j|i2t1
2
p1plnxKx
2
p1plnKx
2
p1plnC
2
p1plnxC)p,...,p(l
ij
ij
Constant )Cln(C 12 = .
∑∑∑∑
∑∑
====
==
−++
−+
−=
−+
+
−−+
=
−+
∂∂
+
−+
∂∂
=∂∂
t
1j jk
j|kt
1j kj
k|jt
1j jk
j|kt
1i ki
k|i
t
1j
jk
j|k
k
t
1i
ki
k|i
kk
p1p
x
p1p
x
2
1
p1p
x2
2
1
p1p
x2
2
p1plnx
p2
p1plnx
pp
l
45
Thus the MLE’s of the pi’s, i.e. the ip̂ ’s, are found by solving the following t equations:
∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t,
for the t unknowns ip̂ for i = 1, 2, …, t, where ∑=
=d
1c
)c(
j|ij|i xx and )c(
ijx is value that Xij takes
on in round c for c = 1, 2, …, d and where
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irrx ifxr
rrx ifrx .
Corollary 6:
Suppose we have the Paired Comparisons SS-experiment with t objects, and that
2
pp
2
1
2
p1pp
jiji
ij
−+=
−+= , then the MLE’s of the pi’s can be found by solving the
following t equations: ∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …,t,
for the t unknowns ip̂ for i = 1,2,…,t, where ∑=
=ijd
1c
)c(
j|ij|i xx and )c(
ijx is value that Xij takes
on in round c for c = 1,2,…,dij and where
<+
>=
0x ifxr
0x ifrx
)c(
ij
)c(
ij
)c(
ij)c(
j|i.
Proof:
Evident from Theorem 6 as if X ~ SS(r, p) then X ~ S(r, r, p).
Corollary 7:
The MLE’s for the pij’s in Theorem 5 and 6 and Corollary 5 and 6 (and from Theorem
4) are given by 2
p̂p̂
2
1
2
p̂1p̂p̂
jiji
ij
−+=
−+= for i,j = 1,2,…, t where the
ip̂ ’s are the
MLE’s of the pi’s as found by Theorem 5 and 6 and Corollary 5 and 6 respectively.
Proof:
This follows from the invariance property of MLE’s.
46
Theorem 7:
If X ~ TNB(r, p, s), then E(X) =
+ΓΓ
−+++++Γ−−−
)2s()r(
)p1,2s,1sr,2(F)1sr(p)p1(
p
r)p1( 12
rs
.
Proof:
By Mathematica we have that:
+ΓΓ−+++++Γ−
+−+−=)s2()r(
)p1,s2,sr1,2(F)sr1(p)p1(
p
r)p1()X(E 12
rs
+ΓΓ−+++++Γ−
−−=)2s()r(
)p1,2s,1sr,2(F)1sr(p)p1(
p
r)p1( 12
rs
)p1,2s,1sr,2(Fp)p1()2s()r(
)1sr(
p
)p1(r12
r1s −+++−+ΓΓ++Γ
−−
= +
)p1,2s,1sr,2(Fp)p1()!1s()!1r(
)!sr(
p
)p1(r12
r1s −+++−+−
+−
−= +
)p1,2s,1sr,2(Fp)p1(1s
sr
p
)p1(r12
r1s −+++−
−
+−
−= +
Theorem 8:
If X ~ S(r, s, p), then E(X) = m(s, 1 – p, r) – m(r, p, s), where:
m(r, p, s) = )p1,2s,1sr,2(Fp)p1(1s
sr
p
)p1(r12
r1s −+++−
−
+−
− + .
Proof:
Let X = X1 – X2 where X1 ~ TNB(s, 1 – p, r) and X2 ~ TNB(r, p, s).
Thus X ~ S(r, s, p) by Theorem 3. Thus E(X) = E(X1 – X2) = E(X1) – E(X2).
Let m(r, p, s) = )p1,2s,1sr,2(Fp)p1(1s
sr
p
)p1(r12
r1s −+++−
−
+−
− + .
Thus by Theorem 7, E(X1) = m(s, 1 – p, r) and E(X2) = m(r, p, s).
Thus E(X) = m(s, 1 – p, r) – m(r, p, s).
47
5.1 The General SL-Model
• Suppose we have the Paired Comparisons S-experiment with t objects, A1, A2, …,
At.
• Let )c(
ijx be the value that Xij takes on in round c for c = 1, 2, …, dij, let
−<+
−>=
jiij
)c(
ij
)c(
ijji
jiij
)c(
ijij)c(
j|irr xifxr
rr xifrx i.e. )c(
j|ix is Ai’s score when competing against
Aj in round c and let ∑=
=ijd
1c
)c(
j|ij|i xx i.e. j|ix is Ai’s cumulative score from all the
rounds it competed against Aj.
• We set 2
pp
2
1
2
p1pp
jiji
ij
−+=
−+= and to estimate the pi’s we solve the
following t equations in t unknowns as found in theorem 6:
∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t.
• The weight of object Ai, pi is thus estimated to be ip̂ for i = 1, 2, …, t.
Preference:
We can say that Ai is preferred to (better than) Aj i.e. Ai � Aj, in one of the following
ways:
1. If all rij’s are equal:
)X̂(E j|i > )X̂(E i|j i.e. E( ijX̂ ) > 0 where i|jj|iij X̂X̂X̂ −= ~ SS(r, ijp̂ )
i.e. )r,p̂,r(m)r,p̂,r(m ijji >
where m(r, p, s) = )p1,2s,1sr,2(Fp)p1(1s
sr
p
)p1(r12
r1s −+++−
−
+−
− +
48
2. To “standardize” the scores for case where rij ‘s are not all equal:
( ) ( )i|jji
j|i
ij
X̂Er
1X̂E
r
1> i.e.:
ji
jiijij
ij
ijjiji
r
)r,p̂,r(m
r
)r,p̂,r(m>
where m(r, p, s) = )p1,2s,1sr,2(Fp)p1(1s
sr
p
)p1(r12
r1s −+++−
−
+−
− +
3. P(Ai wins when competing with Aj) > 0.5 i.e. *
ijp̂ > 0.5
where *
ijp̂ = )p̂
p̂,r1,r1,1(Fp̂p̂
r
1rr
ji
ij
ijji12
r
ij
1r
ji
i
jiij ijji−
+−
−+ − is the MLE of
*
ijp = )p
p,r1,r1,1(Fpp
r
1rr
ji
ij
ijji12
r
ij
1r
ji
i
jiij ijji−
+−
−+ − (see Theorem 2)
4. If all rij’s are equal:
P(Ai scores in a trial when competing with Aj) > 0.5
i.e. ip̂ > jp̂ i.e. 5.0p̂ ij > (see Theorem 5)
With this option, circular triads cannot occur.
We will use method 4 to rank objects in the section where we do a real life application.
5.2 The Binary SL-Model
The binary SL-model works the same as the general SL-model, the only difference being
that )c(
j|ix takes on the value 1 if Ai beat (had higher score than) Aj in round c and 0 if Ai
lost to Aj in round c. Thus ∑=
=ijd
1c
)c(
j|ij|i xx is the number of times Ai beat Aj.
5.3 The DDic01 Binary SL-Model
The binary SL-model may not always lead to weights of objects which yield proper
probabilities (i.e. weights may not all be between 0 and 1 or be able to be transformed to
49
be between 0 and 1 by adding a constant to all weights (our model is shift invariant i.e. if
p1, …, pt is a solution to our model, then so is p1 + c, …, pt + c) as required by theorem 4
to get proper probabilities which we will be required if we want to predict scores.) The
reason for this is, like in many other models for paired comparisons, the SL-model is
sensitive towards having too many zeros in the data. A form of the SL-model to avoid
this limitation is the DDic01 binary SL-model.
The doubled data if compared zeros become ones binary SL-model (DDic01 binary SL-
model) works the same as the binary SL-model, just that firstly all the scores are doubled
i.e. )c(
j|ix takes on the value as 2 if Ai beat (had higher score than) Aj in round c and 0 if Ai
lost to Aj in round c, thus ∑=
=ijd
1c
)c(
j|ij|i xx is two times the number of times Ai beat Aj.
Secondly, if xi|j > 0 and xj|i = 0, we let xj|i = 1, i.e. if objects were compared (hence at least
one of them will have a cumulative score greater than 0 (based on the definition of S-
experiment)) and one of the objects have a cumulative score of 0, we replace it by 1. This
is a common practice in the Method of Paired Comparisons as various models do not
work if an object did not score a single point against another object.
5.4 The DD01 Binary SL-Model
We may find that the DDic01 binary SL-model also may lead to weights of objects which
does not yield proper probabilities, thus we designed the DD01 binary SL-model.
The doubled data zeros become ones binary SL-model (DDic01 binary SL-model) works
the same as the binary SL-model, just that firstly all the scores are doubled i.e. )c(
j|ix takes
on the value as 2 if Ai beat (had higher score than) Aj in round c and 0 if Ai lost to Aj in
round c, thus ∑=
=ijd
1c
)c(
j|ij|i xx is two times the number of times Ai beat Aj. Secondly, if for i
≠ j, xi|j = 0, we let xi|j = 1, i.e. if an object has a cumulative score against another object of
0, we replace it by 1 (weather objects were compared or not).
50
6 Results and Examples Illustrating Properties of the SL-
Model
6.1 Results of the Solution to the SL-Model
The system of ML-equations of the SL-model is:
∑∑==
−+=
−+
t
1j ij
i|jt
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, …, t.
Although the system seems quite simple in nature, all possible attempts to find a general
symbolic solution to the ip̂ ’s failed. We however found the following interesting results
using Mathematica for certain cases of our model.
Theorem 9:
If t = 2 then the solutions of ∑∑==
−+=
−+
2
1j ij
i|j2
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i = 1, 2, are given by
p1 = 1|22|1
1|22|1
xx
xx
+
− and p2 = 0,
or p1 = 1|22|1
1|22|1
x2x2
xx3
+
− and p2 = 0.5,
or p1 = 1|22|1
2|1
xx
x2
+ and p2 = 1,
or p1 = 1|22|1
2|1
xx
x
+ and p2 =
1|22|1
1|2
xx
x
+.
Note: Similar results are present by varying the value of p1.
Proof:
Using Mathematica:
51
u[i_,j_]:=x[i,j]/(p[i]-p[j]+1)
e[i_]:=Sum[u[i,j]-u[j,i],{j,1,2}]
e[1]
x@1, 2D1+ p@1D −p@2D −
x@2, 1D1− p@1D + p@2D
e[2]
−x@1, 2D
1+p@1D − p@2D +x@2, 1D
1− p@1D+ p@2D
Solve[e[1]�0,p[1]]
::p@1D →x@1, 2D + p@2D x@1, 2D − x@2, 1D + p@2D x@2, 1D
x@1, 2D + x@2, 1D >>
p[2]=0
0
Solve[e[1]�0,p[1]]
::p@1D →x@1, 2D − x@2, 1Dx@1, 2D + x@2, 1D >>
p[2]=0.5
0.5
Solve[e[1]�0,p[1]]
::p@1D →3.x@1, 2D − 1.x@2, 1D2.x@1, 2D + 2.x@2, 1D >>
p[2]=1
1
Solve[e[1]�0,p[1]]
::p@1D →2x@1, 2D
x@1, 2D + x@2, 1D >>
p@2D=
x@2,1D
x@1,2D +x@2,1D
x@2, 1Dx@1, 2D + x@2, 1D
Solve[e[1]�0,p[1]]
::p@1D →x@1, 2D
x@1, 2D + x@2, 1D >>
52
Theorem 10:
If t = 3 and x2|3 = x3|2 = 0 then the solutions of ∑∑==
−+=
−+
3
1j ij
i|j3
1j ji
j|i
p̂1p̂
x
p̂1p̂
x for i =
1, 2, 3 are given by:
p1 = 0, p2 = 1|22|1
1|22|1
xx
xx
+
+−and p3 =
1|33|1
1|33|1
xx
xx
+
+−,
or p1 = 0.5, p2 = 1|22|1
1|22|1
x2x2
x3x
+
+−and p3 =
1|33|1
1|33|1
x2x2
x3x
+
+−,
or p1 = 1, p2 = 1|22|1
1|2
xx
x2
+and p3 =
1|33|1
1|3
xx
x2
+,
or p1 – p2 = 1|22|1
1|22|1
xx
xx
+
− and p2 – p3 =
1|33|1
1|33|1
xx
xx
+
−.
Proof:
Using Mathematica:
u[i_,j_]:=x[i,j]/(p[i]-p[j]+1)
e[i_]:=Sum[u[i,j]-u[j,i],{j,1,3}]
e[1]
x@1, 2D1+ p@1D −p@2D +
x@1, 3D1+ p@1D − p@3D −
x@2, 1D1− p@1D + p@2D −
x@3, 1D1− p@1D + p@3D
e[2]
−x@1, 2D
1+p@1D − p@2D +x@2, 1D
1− p@1D+ p@2D +x@2, 3D
1+ p@2D −p@3D −x@3, 2D
1− p@2D +p@3D
e[3]
−x@1, 3D
1+p@1D − p@3D −x@2, 3D
1+ p@2D− p@3D +x@3, 1D
1− p@1D +p@3D +x@3, 2D
1− p@2D +p@3D
x[2,3]=0
0
x[3,2]=0
0
53
p[1]=0
0
Solve[Table[e[i]�0,{i,1,3}],Table[p[i],{i,2,3}]]
::p@2D →−x@1, 2D + x@2, 1Dx@1, 2D + x@2, 1D , p@3D →
−x@1, 3D + x@3, 1Dx@1, 3D + x@3, 1D >>
p[1]=0.5
0.5
Solve[Table[e[i]�0,{i,1,3}],Table[p[i],{i,2,3}]]
::p@2D →−1.x@1, 2D + 3.x@2, 1D2.x@1, 2D + 2.x@2, 1D ,
p@3D →−1.x@1, 3D + 3.x@3, 1D2.x@1, 3D + 2.x@3, 1D >>
p[1]=1
1
Solve[Table[e[i]�0,{i,1,3}],Table[p[i],{i,2,3}]]
::p@2D →2x@2, 1D
x@1, 2D + x@2, 1D , p@3D →2x@3, 1D
x@1, 3D +x@3, 1D >>
Similar results can be found by the following method:
y=p1-p2
z=p1-p3
z-y=p2-p3
e@1D =
x12
1+y+x13
1+z−x21
1−y−x31
1−z
−x21
1−y+
x12
1+ y−
x31
1−z+
x13
1+ z
e@2D = −
x12
1+y+x21
1−y+
x23
1+Hz−yL−
x32
1− Hz−yL
x21
1− y−
x12
1+ y−
x32
1+ y−z+
x23
1− y+ z
e@3D = −
x13
1+z−
x23
1+ Hz−yL+x31
1−z+
x32
1− Hz−yL
54
x31
1− z+
x32
1+ y− z−
x13
1+z−
x23
1− y+ z
x23=0
0
x32=0
0
Solve[e[2]�0,y]
::y→
x12− x21
x12+ x21>>
Solve[e[3]�0,z]
::z→
x13− x31
x13+ x31>>
p1=0
0
p2=p1-y
−x12−x21
x12+x21
p3=p1-z
−x13−x31
x13+x31
We were however unable to find a general solution for the case where t = 3 i.e. where we
do not set certain xi|j’s to 0.
55
6.2 Examples illustrating further Properties of the SL-Model
Example 3:
Suppose we have 3 teams playing a sport. In each game, the two teams play until one of
the teams score 5 points, then that team wins. Suppose the results of the games were as
follows:
Teams Scores
Team 1 against Team 2 3:5
Team 1 against Team 3 5:2
Team 2 against Team 3 4:5
Note: the scores were assigned so that each team gets a turn to win.
Solution:
Calculations were done in Mathematica as follows:
sl[i_,j_]:=x[i,j]/(p[i]+1-p[j])
sr[i_,j_]:=sl[j,i]
s[i_,j_]:=sl[i,j]-sr[i,j]
x[1,2]=3
3
x[2,1]=5
5
x[1,3]=5
5
x[3,1]=2
2
x[2,3]=4
4
x[3,2]=5
5
56
eqns={s[1,2]+s[1,3]==0,s[2,1]+s[2,3]==0,s[3,1]+s[3,2]==0}
: 3
1+ p@1D −p@2D −5
1− p@1D + p@2D +5
1+ p@1D − p@3D −2
1− p@1D + p@3D � 0,
−3
1+p@1D − p@2D +5
1− p@1D+ p@2D +4
1+ p@2D −p@3D −5
1− p@2D +p@3D � 0,
−5
1+p@1D − p@3D −4
1+ p@2D− p@3D +2
1− p@1D +p@3D +5
1− p@2D +p@3D � 0>
weights=FindRoot[eqns,{{p[1],0.5},{p[2],0.5},{p[3],0.5}}]
{p[1]→0.54874,p[2]→0.535442,p[3]→0.415818}
p[1]/. weights
0.54874
p[2]/.weights
0.535442
p[3]/.weights
0.415818
p[i_,j_]:=(p[i]+1-p[j])/2/.weights
p[1,2]
0.506649
p[1,3]
0.566461
p[2,3]
0.559812
pstar[i_,j_]:=Binomial[5+5–1,5]*(1-p[i,j])^(5–1)*
p[i,j]^5*Hypergeometric2F1[1,1-5,1+5,-p[i,j]/(1-p[i,j])]
/.weights
pstar[1,2]
0.51636
pstar[1,3]
0.659765
pstar[2,3]
0.644421
m[r_,p_,s_] := r(1-p)/p-Binomial[r+s,s–1]*(1-p)^(s+1)
*p^r*Hypergeometric2F1[2,r+s+1,s+2,1-p]
57
Ex[i_,j_]:=m[5,1-p[i,j],5]-m[5,p[i,j],5]
Ex[1,2]
0.10025
Ex[1,3]
0.991063
Ex[2,3]
0.893779
The results are as follows:
1p̂ = 0.54874, 2p̂ = 0.535442, 3p̂ = 0.415818.
12p̂ = 0.506649, 13p̂ = 0.566461,
23p̂ = 0.559812.
=*
12p̂ 0.51636, =*
13p̂ 0.659765, =*
23p̂ 0.644421.
)X̂(E 12= 0.10025 ≈ 1, )X̂(E 13
= 0.991063 ≈ 1, )X̂(E 23= 0.893779 ≈ 1.
(Theorem 8 was used to calculate these values in Mathematica.)
Note: Xij = Xi|j – Xj|i, but if we round off )X̂(E ij to the nearest value in the range of Xij,
we find that the actual values of Xij are far from )X̂(E ij . This is because we have only
one observation for each possible pair of teams playing a game, and from their scores, we
see that a circular triad is present. Note we round off to the nearest value in the range and
0 is not in the range, so 0.10025 gets rounded off to 1.
All the ways (1&2, 3, 4) of assigning preferences (see section 5.1) result in ranking the
teams from best to worst as Team 1, Team 2 then Team 3.
58
Score Estimation is done as follows:
Estimated value of
Xij = Xi|j – Xj|i
Estimated value of Xi|j
Estimated value of Xj|i
–5 0 5
–4 1 5
–3 2 5
–2 3 5
–1 4 5
1 5 4
2 5 3
3 5 2
4 5 1
5 5 0
Clearly there is a 1–1 correspondence between values of Xij and pairs of values of (Xi|j,
Xj|i). Thus the estimated scores are given in the following table:
Teams Scores Estimated Scores
Team 1 against Team 2 3:5 4:5
Team 1 against Team 3 5:2 4:5
Team 2 against Team 3 4:5 4:5
Note: the scores were assigned so that each team gets a turn to win, so we cannot expect
the estimated scores to be accurate based on one observation per pair.
Example 4:
Suppose we have 3 teams playing a sport. In each game, the two teams play until one of
the teams score 5 points, then that team wins. Suppose the results of the games were as
follows:
59
Teams Scores
Team 1 against Team 2 5:3
Team 1 against Team 3 3:5
Team 2 against Team 3 5:3
Note: the scores were assigned so that each team gets a turn to win, and all teams are
equally as good.
Solution:
Calculations were done in Mathematica as follows:
sl[i_,j_]:=x[i,j]/(p[i]+1-p[j])
sr[i_,j_]:=sl[j,i]
s[i_,j_]:=sl[i,j]-sr[i,j]
x[1,2]=5
5
x[2,1]=3
3
x[1,3]=3
3
x[3,1]=5
5
x[2,3]=5
5
x[3,2]=3
3
eqns={s[1,2]+s[1,3]==0,s[2,1]+s[2,3]==0,s[3,1]+s[3,2]==0}
60
: 5
1+ p@1D −p@2D −3
1− p@1D + p@2D +3
1+ p@1D − p@3D −5
1− p@1D + p@3D � 0,
−5
1+p@1D − p@2D +3
1− p@1D+ p@2D +5
1+ p@2D −p@3D −3
1− p@2D +p@3D � 0,
−3
1+p@1D − p@3D −5
1+ p@2D− p@3D +5
1− p@1D +p@3D +3
1− p@2D +p@3D � 0>
weights=FindRoot[eqns,{{p[1],0.5},{p[2],0.5},{p[3],0.5}}]
{p[1]→0.5,p[2]→0.5,p[3]→0.5}
p[1]/. weights
0.5
p[2]/.weights
0.5
p[3]/.weights
0.5
p[i_,j_]:=(p[i]+1-p[j])/2/.weights
p[1,2]
0.5
p[1,3]
0.5
p[2,3]
0.5
pstar[i_,j_]:=Binomial[5+5–1,5]*(1-p[i,j])^(5–1)*p[i,j]^5
*Hypergeometric2F1[1,1-5,1+5,-p[i,j]/(1-p[i,j])]/.weights
pstar[1,2]
0.5
pstar[1,3]
0.5
pstar[2,3]
0.5
m[r_,p_,s_] := r(1-p)/p-Binomial[r+s,s–1]*(1-p)^(s+1)
*p^r*Hypergeometric2F1[2,r+s+1,s+2,1-p]
Ex[i_,j_]:=m[5,1-p[i,j],5]-m[5,p[i,j],5]
61
Ex[1,2]
0.
Ex[1,3]
0.
Ex[2,3]
0.
As expected, the results are as follows:
1p̂ = 0.5, 2p̂ = 0.5, 3p̂ = 0.5.
12p̂ = 0.5, 13p̂ = 0.5,
23p̂ = 0.5.
=*
12p̂ 0.5, =*
13p̂ 0.5, =*
23p̂ 0.5.
)X̂(E 12 = 0 ≈ –1 or 1, )X̂(E 13
= 0 ≈ –1 or 1, )X̂(E 23= 0 ≈ –1 or 1.
Note: Xij = Xi|j – Xj|i, but if we round off )X̂(E ij to the nearest value in the range of Xij,
we find that the actual values of Xij are far from )X̂(E ij . This is because we have only
one observation for each possible pair of teams playing a game, and from their scores, we
see that a circular triad is present. Note we round off to the nearest value in the range and
0 is not in the range, so 0 gets rounded off to –1 or 1.
All the ways (1&2, 3, 4) of assigning preferences (see section 5.1) result in a tie between
the three teams. Score Estimation is done as follows:
62
Estimated value of
Xij = Xi|j – Xj|i
Estimated value of Xi|j
Estimated value of Xj|i
–5 0 5
–4 1 5
–3 2 5
–2 3 5
–1 4 5
1 5 4
2 5 3
3 5 2
4 5 1
5 5 0
Clearly there is a 1–1 correspondence between values of Xij and pairs of values of (Xi|j,
Xj|i). Thus the estimated scores are given in the following table:
Teams Scores Estimated Scores
Team 1 against Team 2 5:3 5:4 or 4:5
Team 1 against Team 3 3:5 5:4 or 4:5
Team 2 against Team 3 5:3 5:4 or 4:5
Note: the scores were assigned so that each team gets a turn to win, and all teams are
equally as good.
Example 5:
Suppose we have 3 teams playing a sport. In each game, the two teams play until one of
the teams score 6 points, then that team wins. Suppose the results of the games were as
follows:
63
Teams Scores
Team 1 against Team 2 6:4
Team 1 against Team 3 6:1
Team 2 against Team 3 6:3
Note: the scores were assigned so that team 1 is the best, team 2 is the second best, and
team 3 is the worst.
Solution:
Calculations were done in Mathematica as follows:
sl[i_,j_]:=x[i,j]/(p[i]+1-p[j])
sr[i_,j_]:=sl[j,i]
s[i_,j_]:=sl[i,j]-sr[i,j]
x[1,2]=6
6
x[2,1]=4
4
x[1,3]=6
6
x[3,1]=1
1
x[2,3]=6
6
x[3,2]=3
3
eqns={s[1,2]+s[1,3]==0,s[2,1]+s[2,3]==0,s[3,1]+s[3,2]==0}
: 6
1+ p@1D −p@2D −4
1− p@1D + p@2D +6
1+ p@1D − p@3D −1
1− p@1D + p@3D � 0,
−6
1+p@1D − p@2D +4
1− p@1D+ p@2D +6
1+ p@2D −p@3D −3
1− p@2D +p@3D � 0,
−6
1+p@1D − p@3D −6
1+ p@2D− p@3D +1
1− p@1D +p@3D +3
1− p@2D +p@3D � 0>
64
weights=FindRoot[eqns,{{p[1],0.3},{p[2],0.3},{p[3],0.3}}]
{p[1]→0.959933,p[2]→0.696941,p[3]→0.30025}
p[1]/. weights
0.959933
p[2]/.weights
0.696941
p[3]/.weights
0.30025
p[i_,j_]:=(p[i]+1-p[j])/2/.weights
p[1,2]
0.631496
p[1,3]
0.829841
p[2,3]
0.698346
pstar[i_,j_]:=Binomial[6+6–1,6]*(1-p[i,j])^(6–1)*p[i,j]^6
*Hypergeometric2F1[1,1-6,1+6,-p[i,j]/(1-p[i,j])]/.weights
pstar[1,2]
0.818171
pstar[1,3]
0.99487
pstar[2,3]
0.919888
m[r_,p_,s_] := r(1-p)/p-Binomial[r+s,s–1]*(1-p)^(s+1)
*p^r*Hypergeometric2F1[2,r+s+1,s+2,1-p]
Ex[i_,j_]:=m[6,1-p[i,j],6]-m[6,p[i,j],6]
Ex[1,2]
2.32549
Ex[1,3]
4.76192
Ex[2,3]
3.31115
65
The results are as follows:
1p̂ = 0.959933, 2p̂ = 0.696941, 3p̂ = 0.30025.
12p̂ = 0.631496, 13p̂ = 0.829841, 23p̂ = 0.698346.
=*
12p̂ 0.818171, =*
13p̂ 0.99487, =*
23p̂ 0.919888.
)X̂(E 12 = 2.32549 ≈ 2, )X̂(E 13 = 4.76192 ≈ 5, )X̂(E 23 = 3.31115 ≈ 3.
All the ways (1&2, 3, 4) of assigning preferences (see section 5.1) result in team 1 being
the best, team 2 the second best and team 3 the worst.
Score Estimation is done as follows:
Estimated value of
Xij = Xi|j – Xj|i
Estimated value of Xi|j
Estimated value of Xj|i
–6 0 6
–5 1 6
–4 2 6
–3 3 6
–2 4 6
–1 5 6
1 6 5
2 6 4
3 6 3
4 6 2
5 6 1
6 6 0
66
Clearly there is a 1–1 correspondence between values of Xij and pairs of values of (Xi|j,
Xj|i). Thus the estimated scores are given in the following table:
Teams Scores Estimated Scores
Team 1 against Team 2 6:4 6:4
Team 1 against Team 3 6:1 6:1
Team 2 against Team 3 6:3 6:3
The estimated scores are exactly the scores that were obtained.
Example 6:
Suppose we have 3 teams playing a sport. In each game, team i plays against team j until
team i score rij points or until team j score rji points, whichever occurs first, where r12 = 4,
r21 = 4, r13 = 5, r31 = 5, r23 = 6 and r32 = 6. Suppose the results of the games were as
follows:
Teams Scores
Team 1 against Team 2 3:4
Team 1 against Team 3 5:4
Team 2 against Team 3 5:6
Note: the scores were assigned so that the total number of points a team gains in all the
matches it participates in equals the total number of points the team lost to its opponents
in all the matches it played.
Team Points won Points lost
Team 1 x1|2 + x1|3 = 3 + 5 = 8 x2|1 + x3|1 = 4 + 4 = 8
Team 2 x2|1 + x2|3 = 4 + 5 = 9 x1|2 + x3|2 = 3 + 6 = 9
Team 3 x3|1 + x3|2 = 4 + 6 = 10 x1|3 + x2|3 = 4 + 6 = 10
Also note that we are dealing with a circular triad, thus predictions may not be so good.
67
Solution:
Calculations were done in Mathematica as follows:
sl[i_,j_]:=x[i,j]/(p[i]+1-p[j])
sr[i_,j_]:=sl[j,i]
s[i_,j_]:=sl[i,j]-sr[i,j]
x[1,2]=3
3
x[2,1]=4
4
x[1,3]=5
5
x[3,1]=4
4
x[2,3]=5
5
x[3,2]=6
6
eqns={s[1,2]+s[1,3]==0,s[2,1]+s[2,3]==0,s[3,1]+s[3,2]==0}
: 3
1+ p@1D −p@2D −4
1− p@1D + p@2D +5
1+ p@1D − p@3D −4
1− p@1D + p@3D � 0,
−3
1+p@1D − p@2D +4
1− p@1D+ p@2D +5
1+ p@2D −p@3D −6
1− p@2D +p@3D � 0,
−5
1+p@1D − p@3D −5
1+ p@2D− p@3D +4
1− p@1D +p@3D +6
1− p@2D +p@3D � 0>
weights=FindRoot[eqns,{{p[1],0.5},{p[2],0.5},{p[3],0.5}}]
{p[1]→0.5,p[2]→0.5,p[3]→0.5}
p[1]/. weights
0.5
p[2]/.weights
0.5
p[3]/.weights
68
0.5
p[i_,j_]:=(p[i]+1-p[j])/2/.weights
p[1,2]
0.5
p[1,3]
0.5
p[2,3]
0.5
pstar[i_,j_]:=Binomial[6+6–1,6]*(1-p[i,j])^(6–1)*p[i,j]^6*
Hypergeometric2F1[1,1-6,1+6,-p[i,j]/(1-p[i,j])]/.weights
pstar[1,2]
0.5
pstar[1,3]
0.5
pstar[2,3]
0.5
m[r_,p_,s_] := r(1-p)/p-Binomial[r+s,s–1]*(1-p)^(s+1)
*p^r*Hypergeometric2F1[2,r+s+1,s+2,1-p]
r[1,2]=4
4
r[2,1]=4
4
r[1,3]=5
5
r[3,1]=5
5
r[2,3]=6
6
r[3,2]=6
6
Ex[i_,j_]:=m[r[j,i],1-p[i,j],r[i,j]]-
m[r[j,i],p[i,j],r[i,j]]
69
Ex[1,2]
0.
Ex[1,3]
0.
Ex[2,3]
0.
The results are as follows:
1p̂ = 0.5, 2p̂ = 0.5, 3p̂ = 0.5.
12p̂ = 0.5, 13p̂ = 0.5, 23p̂ = 0.5.
=*
12p̂ 0.5, =*
13p̂ 0.5, =*
23p̂ 0.5.
)X̂(E 12 = 0 ≈ –1 or 1, )X̂(E 13
= 0 ≈ –1 or 1, )X̂(E 23= 0 ≈ –1 or 1.
Note: Xij = Xi|j – Xj|i, but if we round off )X̂(E ij to the nearest value in the range of Xij,
we find that the actual values of Xij are far from )X̂(E ij . This is because we have only
one observation for each possible pair of teams playing a game, and from there scores,
we see that a circular triad is present. Note we round off to the nearest value in the range
and 0 is not in the range, so 0 gets rounded off to –1 or 1.
All the ways (1&2, 3, 4) of assigning preferences (see section 5.1) result in a tie between
the three teams.
70
The Estimated Scores are given in the following table:
Teams Scores Estimated Scores
Team 1 against Team 2 3:4 3:4 or 4:3
Team 1 against Team 3 5:4 4:5 or 5:4
Team 2 against Team 3 5:6 5:6 or 6:5
As mentioned before, the scores were assigned so that the total number of points a team
gains in all the matches it participates in equals the total number of points the team lost to
its opponents in all the matches it played. This illustrates a property of the SL-model, viz.
if for each team, the total points a team gained equals the total points a team lost, then the
SL-model will yield a tie between the teams.
In these examples we just looked at 1 observation per pair of teams. As mentioned, if we
have more than one observation per pair, we use cumulative score of object i out of all
the games he played against object j as our data. In section 7 we are going to do this when
working with real life data in the general SL-model.
71
7 Real Life Application of the SL-Model
7.1 Data
Data was received from the following Tennis Tournaments about the top 20 rated tennis
players for 2004:
1. AAPT Championships - Adelaide
2. Tata Open - Chennai
3. Qatar Open - Doha
4. Heineken Open - Auckland
5. Adidas International - Sydney
6. Australian Open - Melbourne
7. Australian Open - Melbourne
8. Milan Indoors - Milan
9. Siebel Open - San Jose
10. BellSouth Open - Vina del Mar
11. Argentina Open - Buenos Aires
12. Kroger / St. Jude International - Memphis
13. ABN/AMRO World Tennis Tournament - Rotterdam
14. Brasil Open - Costa do Sauipe
15. Open 13 - Marseille
16. Abierto Mexicano Telfonica MoviStar - Acapulco
17. Dubai Open - Dubai
18. Arizona Men's Tennis Championships - Scottsdale
19. Pacific Life Open - Indian Wells
20. Pacific Life Open - Indian Wells
21. NASDAQ-100 Open - Miami
22. Estoril Open - Estoril
23. U.S. Men's Clay Court Championships - Houston
24. Open de la Comunidad Valenciana - Valencia
72
25. Tennis Masters Series - Monte Carlo
26. Open Seat Godo 2004 - Barcelona
27. BMW Open - Munich
28. Telecom Italia Masters - Rome
29. Tennis Masters Series - Hamburg
30. Grand Prix Hassan II - Casablanca
31. Internationaler Raiffeisen Grand Prix - St. Pölten
32. French Open - Paris
33. Gerry Weber Open - Halle
34. The Stella Artois Grass Court Championships - Queen's Club/London
35. Ordina Open - 's-Hertogenbosch
36. The Nottingham Open - Nottingham
37. Wimbledon - London
38. Synsam Swedish Open - Bastad
39. Allianz Suisse Open - Gstaad
40. Campbell's Hall of Fame Tennis Championships - Newport
41. The Priority Telecom Open - Amersfoort
42. Mercedes-Benz Cup - Los Angeles
43. Mercedes Cup - Stuttgart
44. RCA Championships - Indianapolis
45. Generali Open - Kitzbühel
46. Croatia Open - Umag
47. Tennis Masters Series Canada - Toronto
48. Western & Southern Financial Group Masters - Cincinnati
49. Idea Prokom Open - Sopot
50. Olympics - Athens
51. Legg Mason Tennis Classic - Washington D.C.
52. TD Waterhouse Cup - Long Island
53. U.S. Open - New York
54. U.S. Open - New York
55. China Open - Beijing
73
56. Open Romania - Bucharest
57. International Tennis Championships - Delray Beach
58. Thailand Open - Bangkok
59. Campionati Internazionali di Sicilia - Palermo
60. Heineken Open Shanghai - Shanghai
61. Grand Prix de Tennis de Lyon - Lyon
62. AIG Japan Open - Tokyo
63. Open de Moselle - Metz
64. Kremlin Cup - Moscow
65. CA Tennis Trophy - Vienna
66. Tennis Masters Series - Madrid
67. Davidoff Swiss Indoors - Basel
68. St. Petersburg Open - St. Petersburg
69. Stockholm Open - Stockholm
70. BNP Paribas Masters - Paris
71. Tennis Masters Cup - Houston
To do the analysis, only games where one of the top 20 rated tennis players played
against another one of the top 20 rated tennis player could be used. The following results
were thus extracted:
(First half of the year)
(1)Guillermo Coria (ARG) d. Nicolas Kiefer (GER) 7-6(4) 6-3
(3)Carlos Moya (ESP) d. Tommy Robredo (ESP) 6-1 6-2
(7)Lleyton Hewitt (AUS) d. (3)Carlos Moya (ESP) 4-3 ret.
(9)Sebastien Grosjean (FRA) d. Mikhail Youzhny (RUS) 6-1 6-4 7-5
Gaston Gaudio (ARG) d. (20)Tommy Robredo (ESP) 6-3 6-2 7-6(6)
Dominik Hrbaty (SVK) d. Gaston Gaudio (ARG) 6-1 7-5 6-0
(9)Sebastien Grosjean (FRA) d. Dominik Hrbaty (SVK) 2-6 6-4 6-1 6-3
Guillermo Canas (ARG) d. (11)Tim Henman (GBR) 6-7(5) 5-7 7-6(3) 7-5 9-7
(8)David Nalbandian (ARG) d. Guillermo Canas (ARG) 6-4 6-2 6-1
(2)Roger Federer (SUI) d. (15)Lleyton Hewitt (AUS) 4-6 6-3 6-0 6-4
74
Marat Safin (RUS) d. (1)Andy Roddick (USA) 2-6 6-3 7-5 6-7(0) 6-4
(4)Andre Agassi (USA) d. (9)Sebastien Grosjean (FRA) 6-2 2-0 ret.
(2)Roger Federer (SUI) d. (8)David Nalbandian (ARG) 7-5 6-4 5-7 6-3
Marat Safin (RUS) d. (4)Andre Agassi (USA) 7-6(6) 7-6(6) 5-7 1-6 6-3
(2)Roger Federer (SUI) d. Marat Safin (RUS) 7-6(3) 6-4 6-2
Mikhail Youzhny (RUS) d. (8)Dominik Hrbaty (SVK) 6-4 6-3
Joachim Johansson (SWE) d. Nicolas Kiefer (GER) 5-7 7-5 6-2
(6)Vince Spadea (USA) d. (WC)Tommy Haas (GER) 6-4 6-2
(1)Andy Roddick (USA) d. Joachim Johansson (SWE) 6-3 7-6(7)
(1)Guillermo Coria (ARG) d. (2)Carlos Moya (ESP) 6-4 6-1
Joachim Johansson (SWE) d. (8)Nicolas Kiefer (GER) 7-6(5) 6-3
(5)Tim Henman (GBR) d. Tommy Robredo (ESP) 7-5 6-2
(5)Tim Henman (GBR) d. (1)Roger Federer (SUI) 6-3 7-6(9)
(6)Lleyton Hewitt (AUS) d. (5)Tim Henman (GBR) 6-3 6-3
(WC)Guillermo Canas (ARG) d. (6)Gaston Gaudio (ARG) 6-4 6-3
(1)Roger Federer (SUI) d. (WC)Marat Safin (RUS) 7-6(2) 7-6(4)
Mikhail Youzhny (RUS) d. (2)Guillermo Coria (ARG) 4-6 6-3 6-4
(1)Roger Federer (SUI) d. Tommy Robredo (ESP) 6-3 6-4
(4)Vince Spadea (USA) d. (1)Andy Roddick (USA) 6-7(5) 6-3 6-4
(4)Vince Spadea (USA) d. (7)Nicolas Kiefer (GER) 7-5 6-7(5) 6-3
(5)Andre Agassi (USA) d. (31)Dominik Hrbaty (SVK) 6-2 6-4
(3)Andy Roddick (USA) d. (30)(WC)Marat Safin (RUS) 7-6(6) 6-2
(4)Guillermo Coria (ARG) d. (13)Sebastien Grosjean (FRA) 3-6 7-6(2) 6-2
(5)Andre Agassi (USA) d. Mikhail Youzhny (RUS) 7-5 6-2
(5)Andre Agassi (USA) d. (4)Guillermo Coria (ARG) 6-4 7-5
(9)Tim Henman (GBR) d. (3)Andy Roddick (USA) 6-7(6) 7-6(1) 6-3
(1)Roger Federer (SUI) d. (5)Andre Agassi (USA) 4-6 6-3 6-4
(1)Roger Federer (SUI) d. (9)Tim Henman (GBR) 6-3 6-3
Guillermo Canas (ARG) d. (WC)Tommy Haas (GER) 6-1 7-6(6)
Vince Spadea (USA) d. (31)Marat Safin (RUS) 7-6(7) 6-7(4) 6-4
(5)Carlos Moya (ESP) d. (27)Dominik Hrbaty (SVK) 7-5 1-6 6-3
75
Nicolas Kiefer (GER) d. (12)Sebastien Grosjean (FRA) 6-4 6-2
(5)Carlos Moya (ESP) d. (19)Tommy Robredo (ESP) 6-3 6-3
(2)Andy Roddick (USA) d. Guillermo Canas (ARG) 6-3 6-3
(3)Guillermo Coria (ARG) d. Nicolas Kiefer (GER) 6-3 6-3
(2)Andy Roddick (USA) d. (5)Carlos Moya (ESP) 5-7 6-2 7-5
(2)Andy Roddick (USA) d. Vince Spadea (USA) 6-1 6-3
(2)Andy Roddick (USA) d. (3)Guillermo Coria (ARG) 6-7(2) 6-3 6-1
(8)Marat Safin (RUS) d. (4)Tommy Robredo (ESP) 7-6(2) 2-6 7-6(5)
(7)David Nalbandian (ARG) d. Dominik Hrbaty (SVK) 6-3 6-0
(6)Tim Henman (GBR) d. Vince Spadea (USA) 6-7(5) 6-4 7-6(5)
(3)Guillermo Coria (ARG) d. Nicolas Kiefer (GER) 6-0 6-3
(16)Lleyton Hewitt (AUS) d. Gaston Gaudio (ARG) 1-6 7-6(5) 6-1
(6)Tim Henman (GBR) d. (9)Nicolas Massu (CHI) 3-6 6-4 6-3
(3)Guillermo Coria (ARG) d. (7)David Nalbandian (ARG) 6-4 6-3
(3)Guillermo Coria (ARG) d. Marat Safin (RUS) 6-4 1-6 6-3
(13)Gaston Gaudio (ARG) d. (2)Carlos Moya (ESP) 6-4 6-4
(8)Tommy Robredo (ESP) d.(13)Gaston Gaudio (ARG) 6-3 4-6 6-2 3-6 6-3
Guillermo Canas (ARG) d. (2)Andy Roddick (USA) 7-6(7) 6-1
(8)Nicolas Massu (CHI) d. Marat Safin (RUS) 6-3 7-5
(5)David Nalbandian (ARG) d. Vince Spadea (USA) 6-4 6-3
(6)Carlos Moya (ESP) d. (5)David Nalbandian (ARG) 6-3 6-3 6-1
(1)Roger Federer (SUI) d. Gaston Gaudio (ARG) 6-1 5-7 6-4
(WC)Tommy Haas (GER) d. Vince Spadea (USA) 6-0 ret.
Marat Safin (RUS) d. (8)Sebastien Grosjean (FRA) 7-6(6) 7-5
Mikhail Youzhny (RUS) d. Nicolas Kiefer (GER) 6-4 6-7(2) 6-2
(17)Lleyton Hewitt (AUS) d. (WC)Tommy Haas (GER) 6-4 7-5
(2)Guillermo Coria (ARG) d. (16)Tommy Robredo (ESP) 7-6(2) 6-4
(1)Roger Federer (SUI) d. (7)Carlos Moya (ESP) 6-4 6-3
(1)Roger Federer (SUI) d. (17)Lleyton Hewitt (AUS) 6-0 6-4
(1)Roger Federer (SUI) d. (2)Guillermo Coria (ARG) 4-6 6-4 6-2 6-3
Gaston Gaudio (ARG) d. Guillermo Canas (ARG) 6-2 2-6 4-6 6-3 6-2
76
(1)Roger Federer (SUI) d. Nicolas Kiefer (GER) 6-3 6-4 7-6(6)
(17)Tommy Robredo (ESP) d. (11)Nicolas Massu (CHI) 6-2 6-0 6-2
(8)David Nalbandian (ARG) d. (20)Marat Safin (RUS) 7-5 6-4 6-7(5) 6-3
(5)Carlos Moya (ESP) d. (17)Tommy Robredo (ESP) 7-6(8) 6-4 6-2
Gaston Gaudio (ARG) d. (12)Lleyton Hewitt (AUS) 6-3 6-2 6-2
(3)Guillermo Coria (ARG) d. (5)Carlos Moya (ESP) 7-5 7-6(3) 6-3
Gaston Gaudio (ARG) d. (8)David Nalbandian (ARG) 6-3 7-6(5) 6-0
(3)Guillermo Coria (ARG) d. (9)Tim Henman (GBR) 3-6 6-4 6-0 7-5
Gaston Gaudio (ARG) d. (3)Guillermo Coria (ARG) 0-6 3-6 6-4 6-1 8-6
(1)Roger Federer (SUI) d. Mikhail Youzhny (RUS) 6-2 6-1
(1)Andy Roddick (USA) d. (6)Lleyton Hewitt (AUS) 7-6(7) 6-3
(1)Andy Roddick (USA) d. (5)Sebastien Grosjean (FRA) 7-6(4) 6-4
(4)Tommy Robredo (ESP) d. Guillermo Canas (ARG) 7-5 1-6 7-5
(7)Lleyton Hewitt (AUS) d. (9)Carlos Moya (ESP) 6-4 6-2 4-6 7-6(3)
(1)Roger Federer (SUI) d. (7)Lleyton Hewitt (AUS) 6-1 6-7(1) 6-0 6-4
(1)Roger Federer (SUI) d. (10)Sebastien Grosjean (FRA) 6-2 6-3 7-6(6)
(1)Roger Federer (SUI) d. (2)Andy Roddick (USA) 4-6 7-5 7-6(3) 6-4
(Second half of the year)
Nicolas Kiefer (GER) d. (4)Dominik Hrbaty (SVK) 7-6(0) 4-6 6-2
Tommy Haas (GER) d. (1)Andre Agassi (USA) 7-6(5) 6-7(6) 6-3
Tommy Haas (GER) d. Nicolas Kiefer (GER) 7-6(6) 6-4
Guillermo Canas (ARG) d. (2)Gaston Gaudio (ARG) 5-7 6-2 6-0 1-6 6-3
(6)Dominik Hrbaty (SVK) d. (11)Joachim Johansson (SWE) 7-6(9) 4-6 7-6(1)
(1)Andy Roddick (USA) d. (6)Dominik Hrbaty (SVK) 6-2 6-3
(1)Andy Roddick (USA) d. (12)Nicolas Kiefer (GER) 6-2 6-3
(3)Nicolas Massu (CHI) d. (2)Gaston Gaudio (ARG) 7-6(3) 6-4
Mikhail Youzhny (RUS) d. (6)David Nalbandian (ARG) 3-6 6-3 6-4
(10)Andre Agassi (USA) d. Tommy Haas (GER) 4-6 6-4 6-4
Nicolas Kiefer (GER) d. (15)Marat Safin (RUS) 6-7(3) 6-4 7-6(2)
Nicolas Kiefer (GER) d. (4)Carlos Moya (ESP) 6-4 2-6 6-4
(2)Andy Roddick (USA) d. Nicolas Kiefer (GER) 7-5 6-3
77
(1)Roger Federer (SUI) d. (2)Andy Roddick (USA) 7-5 6-3
Dominik Hrbaty (SVK) d. (1)Roger Federer (SUI) 1-6 7-6(7) 6-4
Mikhail Youzhny (RUS) d. (13)Nicolas Massu (CHI) 6-3 3-6 6-3
Nicolas Kiefer (GER) d. Joachim Johansson (SWE) 6-3 7-6(2)
(2)Andy Roddick (USA) d. Nicolas Kiefer (GER) 6-4 6-4
(10)Lleyton Hewitt (AUS) d. (5)Tim Henman (GBR) 6-1 6-4
(10)Lleyton Hewitt (AUS) d. (14)Marat Safin (RUS) 6-4 6-4
(11)Andre Agassi (USA) d. (4)Carlos Moya (ESP) 7-6(12) 6-3
(2)Andy Roddick (USA) d. (WC)Tommy Haas (GER) 6-3 6-3
(10)Lleyton Hewitt (AUS) d. Tommy Robredo (ESP) 6-3 6-2
(11)Andre Agassi (USA) d. (2)Andy Roddick (USA) 7-5 6-7(2) 7-6(2)
(11)Andre Agassi (USA) d. (10)Lleyton Hewitt (AUS) 6-3 3-6 6-2
(10)Nicolas Massu (CHI) d. Vince Spadea (USA) 7-6(3) 6-2
(2)Andy Roddick (USA) d. Tommy Haas (GER) 4-6 6-3 9-7
Mikhail Youzhny (RUS) d. (14)Nicolas Kiefer (GER) 6-2 3-6 6-2
(10)Nicolas Massu (CHI) d. (3)Carlos Moya (ESP) 6-2 7-5
Mikhail Youzhny (RUS) d. (8)David Nalbandian (ARG) 6-7(4) 6-4 7-5 2-6 6-4
Tommy Haas (GER) d. (12)Sebastien Grosjean (FRA) 6-4 6-4 1-6 6-1
(2)Andy Roddick (USA) d. (29)Guillermo Canas (ARG) 6-1 6-3 6-3
(5)Tim Henman (GBR) d. (19)Nicolas Kiefer (GER) 6-7(5) 6-3 6-1 6-7(4) 3-0 ret.
(2)Andy Roddick (USA) d. (18)Tommy Robredo (ESP) 6-3 6-2 6-4
(1)Roger Federer (SUI) d. (6)Andre Agassi (USA) 6-3 2-6 7-5 3-6 6-3
(5)Tim Henman (GBR) d. (22)Dominik Hrbaty (SVK) 6-1 7-5 5-7 6-2
(4)Lleyton Hewitt (AUS) d. Tommy Haas (GER) 6-2 6-2 6-2
(28)Joachim Johansson (SWE) d. (2)Andy Roddick (USA) 6-4 6-4 3-6 2-6 6-4
(1)Roger Federer (SUI) d. (5)Tim Henman (GBR) 6-3 6-4 6-4
(4)Lleyton Hewitt (AUS) d. (28)Joachim Johansson (SWE) 6-4 7-5 6-3
(1)Roger Federer (SUI) d. (4)Lleyton Hewitt (AUS) 6-0 7-6(3) 6-0
Mikhail Youzhny (RUS) d. (8)Dominik Hrbaty (SVK) 6-4 6-2
(5)Marat Safin (RUS) d. Mikhail Youzhny (RUS) 7-6(4) 7-5
(2)Andy Roddick (USA) d. (3)Marat Safin (RUS) 7-6(1) 6-7(0) 7-6(2)
78
(1)Roger Federer (SUI) d. (2)Andy Roddick (USA) 6-4 6-0
(6)Guillermo Canas (ARG) d. (1)David Nalbandian (ARG) 6-4 2-6 6-3
(6)Guillermo Canas (ARG) d. Tommy Haas (GER) 6-4 6-3
(7)Joachim Johansson (SWE) d. Guillermo Canas (ARG) 7-6(3) 7-5
(2)Andre Agassi (USA) d. (14)Vince Spadea (USA) 6-1 6-3
(2)Andre Agassi (USA) d. (8)Tommy Robredo (ESP) 6-7(3) 6-3 6-2
(3)Marat Safin (RUS) d. (2)Andre Agassi (USA) 6-3 7-6(4)
(3)Marat Safin (RUS) d. (4)David Nalbandian (ARG) 6-2 6-4 6-3
(4)David Nalbandian (ARG) d. Vince Spadea (USA) 6-4 6-4
(4)David Nalbandian (ARG) d. (7)Nicolas Massu (CHI) 6-3 6-4
(1)Andre Agassi (USA) d. (4)Tommy Haas (GER) 7-6(5) 7-6(4)
Mikhail Youzhny (RUS) d. (3)Tim Henman (GBR) 7-5 6-1
(13)Guillermo Canas (ARG) d. (18)Tommy Haas (GER) 7-6(4) 6-2
(2)Lleyton Hewitt (AUS) d. (14)Nicolas Massu (CHI) 4-3 ret.
(6)Marat Safin (RUS) d. (2)Lleyton Hewitt (AUS) 6-4 7-6(2)
(6)Marat Safin (RUS) d. (13)Guillermo Canas (ARG) 6-2 7-6(5)
(1)Roger Federer (SUI) d. (8)Gaston Gaudio (ARG) 6-1 7-6(4)
(3)Lleyton Hewitt (AUS) d. (5)Carlos Moya (ESP) 6-7(5) 6-2 6-4
(4)Marat Safin (RUS) d. (6)Guillermo Coria (ARG) 6-1 6-4
(2)Andy Roddick (USA) d. (7)Tim Henman (GBR) 7-5 7-6(6)
(5)Carlos Moya (ESP) d. (8)Gaston Gaudio (ARG) 6-3 6-4
(1)Roger Federer (SUI) d. (3)Lleyton Hewitt (AUS) 6-3 6-4
(7)Tim Henman (GBR) d. (6)Guillermo Coria (ARG) 6-2 6-2
(2)Andy Roddick (USA) d. (4)Marat Safin (RUS) 7-6(7) 7-6(4)
(1)Roger Federer (SUI) d. (5)Carlos Moya (ESP) 6-3 3-6 6-3
(3)Lleyton Hewitt (AUS) d. (8)Gaston Gaudio (ARG) 6-2 6-1
(2)Andy Roddick (USA) d. (6)Guillermo Coria (ARG) 7-6(4) 6-3
(4)Marat Safin (RUS) d. (7)Tim Henman (GBR) 6-2 7-6(2)
(3)Lleyton Hewitt (AUS) d. (2)Andy Roddick (USA) 6-3 6-2
(1)Roger Federer (SUI) d. (4)Marat Safin (RUS) 6-3 7-6(18)
(1)Roger Federer (SUI) d. (3)Lleyton Hewitt (AUS) 6-3 6-2
79
7.2 Methodology
In sections 7.3 till 7.6, the ranks obtained by the various SL-models are compared to the
official ATP ranks. In section 7.7, the ranks obtained by the various SL-models are
compared to the ranks obtained by various other paired comparisons models. To do these
comparisons, we work out two measures of association viz. Kendal’s Tau and
Spearman’s Rho, between the relevant two sets of ranks. We also do the relevant tests of
significance based on these measures of association.
The measures of association are interpreted as follows:
1. It equals 1 if the agreement is perfect.
2. It equals –1 if the disagreement is perfect (exact inverse order).
3. It equals 0 or close to 0 if one of the rankings is not associated with the other.
4. In other cases the proximity of the index to one of the three extreme points
reflects the degree of association.
Kendal’s Tau is calculated as follows:
For each pair of objects, an agreement is if two sets of rankings rank the two object in the
same order i.e. if the object ranked higher in the one ranking is also ranked higher in the
second ranking e.g. in ranking one, object one is ranked 4th and object two is ranked 7
th
and in ranking two, object one is ranked 5th and object two is ranked 6
th. A disagreement
is if two sets of rankings rank the two object in the reverse order i.e. if the object ranked
higher in the one ranking is ranked lower in the other ranking e.g. in ranking one, object
one is ranked 4th and object two is ranked 7
th and in ranking two, object one is ranked 6
th
and object two is ranked 5th.
Kendal’s τ =N
DA
DA
DA −=
+−
where A is number of agreements, D is the number of
disagreements and N is the number of pairs of objects i.e. N = 2
)1n(n − where n is the
number of objects. We thus let:
80
−
=jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
and then calculate τ as ∑
∑
<
<
ji
2
ij
ji
ij
a
a
.
Spearman’s Rho is calculated as follows:
nn
d61
3
2
i
−−=ρ ∑
, where di is the rank of object i in the first ranking minus the rank of
object i in the second ranking, and n is the number of objects.
We thus conduct the following tests on significance:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
1. Using Kendal’s Tau:
S = A – D = Nτ 18
)5n2)(1n(n2 +−=σ
2
SSz
σ=
σ=
2. Use Spearman’s Rho:
)1n(
12
−=σ
2z
σ
ρ=
σρ
=
Reject H0 if |z| > z(1 + α)/2 where P(Z<zγ = γ).
If we reject H0, then we conclude that at a 100α% significance level, there is sufficient
evidence to say that there is an association between the ranks obtained by two sets of
ranks. (If τ, ρ > 0 positive association and if τ, ρ < 0 negative association.)
7.3 Real Life Application of the General SL-Model
In the general SL-model, we work with cumulative scores obtained by object i when
competing against object j. This data for 2004 was thus summarised on the next page:
Cumulative score of ↓ when
playing against →
(2004)
Roger F
ederer
Andy Roddick
Lleyton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joachim
Johansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjea
n
Mikhail Y
ouzhny
Tommy Haas
Nico
las M
assu
Vince S
padea
Nico
las K
iefer
Roger Federer 0 49 101 46 27 39 22 40 24 30 0 0 12 16 19 12 0 0 0 19
Andy Roddick 33 0 18 65 18 30 31 18 0 0 37 37 18 12 13 0 31 0 26 37
Lleyton Hewitt 47 21 0 22 45 24 0 11 0 33 0 19 12 0 0 0 31 4 0 0
Marat Safin 33 66 21 0 0 13 25 39 37 0 13 0 16 0 14 14 0 8 17 17
Carlos Moya 19 14 34 0 0 0 19 9 18 20 0 0 43 14 0 0 0 7 0 14
Tim Henman 30 30 11 8 0 0 27 0 0 0 32 0 13 24 0 6 0 15 19 27
Guillermo Coria 15 20 0 18 32 26 0 9 12 23 0 0 13 0 16 13 0 0 0 37
Andre Agassi 36 20 15 37 13 0 13 0 0 0 0 0 18 12 8 13 46 0 12 0
David Nalbandian 19 0 0 34 7 0 7 0 0 9 31 0 0 12 0 39 0 12 24 0
Gaston Gaudio 19 0 34 0 19 0 23 0 19 0 49 0 39 6 0 0 0 10 0 0
Guillermo Canas 0 26 0 8 0 34 0 0 21 55 0 11 16 0 0 0 38 0 0 0
Joachim Johansson 0 32 12 0 0 0 0 0 0 0 14 0 0 18 0 0 0 0 0 40
Tommy Robredo 7 9 5 18 21 7 10 12 0 36 15 0 0 0 0 0 0 18 0 0
Dominik Hrbaty 7 5 0 0 14 15 0 6 3 19 0 18 0 0 14 13 0 0 0 14
Sebastien Grosjean 11 10 0 11 0 0 14 2 0 0 0 0 0 20 0 19 15 0 0 6
Mikhail Youzhny 3 0 0 11 0 13 16 7 42 0 0 0 0 24 10 0 0 15 0 33
Tommy Haas 0 22 15 0 0 0 0 45 0 0 22 0 0 0 19 0 0 0 12 13
Nicolas Massu 0 0 3 13 13 13 0 0 7 13 0 0 4 0 0 12 0 0 13 0
Vince Spadea 0 22 0 19 0 17 0 4 15 0 0 0 0 0 0 0 12 8 0 19
Nicolas Kiefer 13 21 0 19 14 18 18 0 0 0 0 36 0 17 12 23 10 0 15 0
82
The weights and ranks obtained using the general SL-model was calculated in
Mathematica as follows:
Y={{0,49,101,46,27,39,22,40,24,30,0,0,12,16,19,12,0,0,0,19},{33,0,18,65,18,30,31,18,0,0,37,37,18,12,13,0,31,0,26,37},{47,21,0,22,45,24,0,11,0,33,0,19,12,0,0,0,31,4,0,0},{33,66,21,0,0,13,25,39,37,0,13,0,16,0,14,14,0,8,17,17},{19,14,34,0,0,0,19,9,18,20,0,0,43,14,0,0,0,7,0,14},{30,30,11,8,0,0,27,0,0,0,32,0,13,24,0,6,0,15,19,27},{15,20,0,18,32,26,0,9,12,23,0,0,13,0,16,13,0,0,0,37},{36,20,15,37,13,0,13,0,0,0,0,0,18,12,8,13,46,0,12,0},{19,0,0,34,7,0,7,0,0,9,31,0,0,12,0,39,0,12,24,0},{19,0,34,0,19,0,23,0,19,0,49,0,39,6,0,0,0,10,0,0},{0,26,0,8,0,34,0,0,21,55,0,11,16,0,0,0,38,0,0,0},{0,32,12,0,0,0,0,0,0,0,14,0,0,18,0,0,0,0,0,40},{7,9,5,18,21,7,10,12,0,36,15,0,0,0,0,0,0,18,0,0},{7,5,0,0,14,15,0,6,3,19,0,18,0,0,14,13,0,0,0,14},{11,10,0,11,0,0,14,2,0,0,0,0,0,20,0,19,15,0,0,6},{3,0,0,11,0,13,16,7,42,0,0,0,0,24,10,0,0,15,0,33},{0,22,15,0,0,0,0,45,0,0,22,0,0,0,19,0,0,0,12,13},{0,0,3,13,13,13,0,0,7,13,0,0,4,0,0,12,0,0,13,0},{0,22,0,19,0,17,0,4,15,0,0,0,0,0,0,0,12,8,0,19},{13,21,0,19,14,18,18,0,0,0,0,36,0,17,12,23,10,0,15,0}} y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.5},{i,1,20}]]
{p[1]→0.857262,p[2]→0.699348,p[3]→0.677667,p[4]→0.667475,p[
5]→0.603827,p[6]→0.618657,p[7]→0.648523,p[8]→0.737597,p[9]→
0.623594,p[10]→0.576848,p[11]→0.592005,p[12]→0.564243,p[13]
→0.512716,p[14]→0.462957,p[15]→0.556654,p[16]→0.626464,p[17
]→0.542551,p[18]→0.567684,p[19]→0.535121,p[20]→0.5}
83
The weights of the objects and the ranks are summarised in the following table:
ATP Race
Standings For
11/22/04 Player Country
2004 SL-
Model
Weight
2004 SL-
Model
Rank
1 Federer, Roger SUI 0.857262 1
2 Roddick, Andy USA 0.699348 3
3 Hewitt, Lleyton AUS 0.677667 4
4 Safin, Marat RUS 0.667475 5
5 Moya, Carlos ESP 0.603827 10
6 Henman, Tim GBR 0.618657 9
7 Coria, Guillermo ARG 0.648523 6
8 Agassi, Andre USA 0.737597 2
9 Nalbandian, David ARG 0.623594 8
10 Gaudio, Gaston ARG 0.576848 12
11 Canas, Guillermo ARG 0.592005 11
12 Johansson, Joachim SWE 0.564243 14
13 Robredo, Tommy ESP 0.512716 18
14 Hrbaty, Dominik SVK 0.462957 20
15 Grosjean, Sebastien FRA 0.556654 15
16 Youzhny, Mikhail RUS 0.626464 7
17 Haas, Tommy GER 0.542551 16
18 Massu, Nicolas CHI 0.567684 13
19 Spadea, Vincent USA 0.535121 17
20 Kiefer, Nicolas GER 0.5 19
To see how the general SL-model compares to the official ranking, we calculated
Kendal's τ and Spearman's ρ and used them to test the association between the general
SL-model ranks and the official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2004 SL-M
odel R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2004 SL-Model Rank 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 3 4 1 1
Marat Safin 4 5 1 1 1
Carlos Moya 5 10 1 1 1 1
Tim Henman 6 9 1 1 1 1 –1
Guillermo Coria 7 6 1 1 1 1 –1 –1
Andre Agassi 8 2 1 –1 –1 –1 –1 –1 –1
David Nalbandian 9 8 1 1 1 1 –1 –1 1 1
Gaston Gaudio 10 12 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 –1
Joachim Johansson 12 14 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 13 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 20 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 16 7 1 1 1 1 –1 –1 1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 16 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 18 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1 1 –1
Vince Spadea 19 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
85
We let:
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij ,
then we get the results seen on the previous table and we can calculate τ as ∑
∑
<
<
ji
2
ij
ji
ij
a
a
.
τ = 0.65263158
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 124
z = 4.02309124
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the 2004 data, and the ATP ranks.
86
Player
ATP Race
Standings For
11/22/04
2004 SL-
Model
Rank
Squared difference
of the ranks
2
id
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 3 4 1
Safin, Marat 4 5 1
Moya, Carlos 5 10 25
Henman, Tim 6 9 9
Coria, Guillermo 7 6 1
Agassi, Andre 8 2 36
Nalbandian, David 9 8 1
Gaudio, Gaston 10 12 4
Canas, Guillermo 11 11 0
Johansson, Joachim 12 14 4
Robredo, Tommy 13 18 25
Hrbaty, Dominik 14 20 36
Grosjean, Sebastien 15 15 0
Youzhny, Mikhail 16 7 81
Haas, Tommy 17 16 1
Massu, Nicolas 18 13 25
Spadea, Vincent 19 17 4
Kiefer, Nicolas 20 19 1
Total 256
ρ = 0.807519
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.807519
87
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.519893
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the 2004 data, and the ATP ranks.
We thus see that the test for association between the general SL-model ranks and the official
ranks using Kendal's τ and the test using Spearman's ρ both indicated an association between
the two sets of ranks. The value of τ was not that high, so we decided to investigate if it is
perhaps due to the official ranks possibly give more weight to more recent tournaments. We
thus did the same analysis on the data from the tournaments from the first half of the year and
that of the second half of the year. Again, the data using cumulative scores was calculated but
this time just from tournaments from the first half of 2004.
Cumulative score of ↓
when playing against
→
(First half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 24 58 33 12 21 22 16 24 17 0 0 12 0 19 12 0 0 0 19
Andy Roddick 21 0 13 31 18 16 18 0 0 0 19 13 0 0 13 0 0 0 26 0
Lleyton Hewitt 29 9 0 0 27 12 0 0 0 21 0 0 0 0 0 0 13 0 0 0
Marat Safin 24 35 0 0 0 0 13 26 19 0 0 0 16 0 14 0 0 8 17 0
Carlos Moya 7 14 21 0 0 0 19 0 18 8 0 0 43 14 0 0 0 0 0 0
Tim Henman 19 19 6 0 0 0 15 0 0 0 32 0 13 0 0 0 0 15 19 0
Guillermo Coria 15 11 0 13 32 22 0 9 12 23 0 0 13 0 16 13 0 0 0 37
Andre Agassi 13 0 0 28 0 0 13 0 0 0 0 0 0 12 8 13 0 0 0 0
David Nalbandian 19 0 0 25 7 0 7 0 0 9 18 0 0 12 0 0 0 0 12 0
Gaston Gaudio 12 0 31 0 12 0 23 0 19 0 31 0 39 6 0 0 0 0 0 0
Guillermo Canas 0 19 0 0 0 34 0 0 7 31 0 0 16 0 0 0 13 0 0 0
Joachim Johansson 0 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 31
Tommy Robredo 7 0 0 18 21 7 10 0 0 36 15 0 0 0 0 0 0 18 0 0
Dominik Hrbaty 0 0 0 0 14 0 0 6 3 19 0 0 0 0 14 7 0 0 0 0
Sebastien Grosjean 11 10 0 11 0 0 14 2 0 0 0 0 0 20 0 19 0 0 0 6
Mikhail Youzhny 3 0 0 0 0 0 16 7 0 0 0 0 0 12 10 0 0 0 0 18
Tommy Haas 0 0 9 0 0 0 0 0 0 0 7 0 0 0 0 0 0 0 12 0
Nicolas Massu 0 0 0 13 0 13 0 0 0 0 0 0 4 0 0 0 0 0 0 0
Vince Spadea 0 22 0 19 0 17 0 0 7 0 0 0 0 0 0 0 12 0 0 19
Nicolas Kiefer 13 0 0 0 0 0 18 0 0 0 0 23 0 0 12 13 0 0 15 0
89
The weights and ranks obtained using the general SL-model for the data from the first half of
2004 was calculated as before in Mathematica.
Y={{0,24,58,33,12,21,22,16,24,17,0,0,12,0,19,12,0,0,0,19},{21,0,13,31,18,16,18,0,0,0,19,13,0,0,13,0,0,0,26,0},{29,9,0,0,27,12,0,0,0,21,0,0,0,0,0,0,13,0,0,0},{24,35,0,0,0,0,13,26,19,0,0,0,16,0,14,0,0,8,17,0},{7,14,21,0,0,0,19,0,18,8,0,0,43,14,0,0,0,0,0,0},{19,19,6,0,0,0,15,0,0,0,32,0,13,0,0,0,0,15,19,0},{15,11,0,13,32,22,0,9,12,23,0,0,13,0,16,13,0,0,0,37},{13,0,0,28,0,0,13,0,0,0,0,0,0,12,8,13,0,0,0,0},{19,0,0,25,7,0,7,0,0,9,18,0,0,12,0,0,0,0,12,0},{12,0,31,0,12,0,23,0,19,0,31,0,39,6,0,0,0,0,0,0},{0,19,0,0,0,34,0,0,7,31,0,0,16,0,0,0,13,0,0,0},{0,9,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,31},{7,0,0,18,21,7,10,0,0,36,15,0,0,0,0,0,0,18,0,0},{0,0,0,0,14,0,0,6,3,19,0,0,0,0,14,7,0,0,0,0},{11,10,0,11,0,0,14,2,0,0,0,0,0,20,0,19,0,0,0,6},{3,0,0,0,0,0,16,7,0,0,0,0,0,12,10,0,0,0,0,18},{0,0,9,0,0,0,0,0,0,0,7,0,0,0,0,0,0,0,12,0},{0,0,0,13,0,13,0,0,0,0,0,0,4,0,0,0,0,0,0,0},{0,22,0,19,0,17,0,0,7,0,0,0,0,0,0,0,12,0,0,19},{13,0,0,0,0,0,18,0,0,0,0,23,0,0,12,13,0,0,15,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.5},{i,1,20}]]
{p[1]→0.841649,p[2]→0.701305,p[3]→0.596944,p[4]→0.640939,p[5]
→0.652591,p[6]→0.638365,p[7]→0.717001,p[8]→0.806532,p[9]→0.68
109,p[10]→0.668278,p[11]→0.628319,p[12]→0.611016,p[13]→0.5720
68,p[14]→0.559451,p[15]→0.594409,p[16]→0.570753,p[17]→0.45036
6,p[18]→0.46682,p[19]→0.585877,p[20]→0.5}
90
Thus the following results were obtained:
ATP Race
Standings
For
11/22/04 Player Country
1st half of
2004 SL-
Model
Weight
1st half of
2004 SL-
Model
Rank
1 Federer, Roger SUI 0.841649 1
2 Roddick, Andy USA 0.701305 4
3 Hewitt, Lleyton AUS 0.596944 12
4 Safin, Marat RUS 0.640939 8
5 Moya, Carlos ESP 0.652591 7
6 Henman, Tim GBR 0.638365 9
7 Coria, Guillermo ARG 0.717001 3
8 Agassi, Andre USA 0.806532 2
9 Nalbandian, David ARG 0.68109 5
10 Gaudio, Gaston ARG 0.668278 6
11 Canas, Guillermo ARG 0.628319 10
12 Johansson, Joachim SWE 0.611016 11
13 Robredo, Tommy ESP 0.572068 15
14 Hrbaty, Dominik SVK 0.559451 17
15 Grosjean, Sebastien FRA 0.594409 13
16 Youzhny, Mikhail RUS 0.570753 16
17 Haas, Tommy GER 0.450366 20
18 Massu, Nicolas CHI 0.46682 19
19 Spadea, Vincent USA 0.585877 14
20 Kiefer, Nicolas GER 0.5 18
As before, we then went on to calculate Kendal's τ and Spearman's ρ and used them to test
the association between the general SL-model (using just 1st half of 2004 data) ranks and the
official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
1st h
alf of 2
004 SL-M
odel
Rank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1st half of 2004 SL-
Model Rank
1 4 12 8 7 9 3 2 5 6 10 11 15 17 13 16 20 19 14 18
Roger Federer 1 1
Andy Roddick 2 4 1
Lleyton Hewitt 3 12 1 1
Marat Safin 4 8 1 1 –1
Carlos Moya 5 7 1 1 –1 –1
Tim Henman 6 9 1 1 –1 1 1
Guillermo Coria 7 3 1 –1 –1 –1 –1 –1
Andre Agassi 8 2 1 –1 –1 –1 –1 –1 –1
David Nalbandian 9 5 1 1 –1 –1 –1 –1 1 1
Gaston Gaudio 10 6 1 1 –1 –1 –1 –1 1 1 1
Guillermo Canas 11 10 1 1 –1 1 1 1 1 1 1 1
Joachim Johansson 12 11 1 1 –1 1 1 1 1 1 1 1 1
Tommy Robredo 13 15 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 17 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 13 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 16 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 18 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Vince Spadea 19 14 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 –1 –1
Nicolas Kiefer 20 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
92
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.621053
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 118
z = 3.828426
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the first half of 2004 data, and the
ATP ranks.
93
Player
ATP Race
Standings For
11/22/04
1st half of
2004 SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 4 4
Hewitt, Lleyton 3 12 81
Safin, Marat 4 8 16
Moya, Carlos 5 7 4
Henman, Tim 6 9 9
Coria, Guillermo 7 3 16
Agassi, Andre 8 2 36
Nalbandian, David 9 5 16
Gaudio, Gaston 10 6 16
Canas, Guillermo 11 10 1
Johansson, Joachim 12 11 1
Robredo, Tommy 13 15 4
Hrbaty, Dominik 14 17 9
Grosjean, Sebastien 15 13 4
Youzhny, Mikhail 16 16 0
Haas, Tommy 17 20 9
Massu, Nicolas 18 19 1
Spadea, Vincent 19 14 25
Kiefer, Nicolas 20 18 4
Total 256
ρ = 0.807519
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.807519
94
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.519893
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the first half of 2004 data, and the
ATP ranks.
The cumulative scores were calculated from tournaments from the second half of 2004, as
seen on the next page.
Cumulative score of ↓
when playing against
→
(Second half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 25 43 13 15 18 0 24 0 13 0 0 0 16 0 0 0 0 0 0
Andy Roddick 12 0 5 34 0 14 13 18 0 0 18 24 18 12 0 0 31 0 0 37
Lleyton Hewitt 18 12 0 22 18 12 0 11 0 12 0 19 12 0 0 0 18 4 0 0
Marat Safin 9 31 21 0 0 13 12 13 18 0 13 0 0 0 0 14 0 0 0 17
Carlos Moya 12 0 13 0 0 0 0 9 0 12 0 0 0 0 0 0 0 7 0 14
Tim Henman 11 11 5 8 0 0 12 0 0 0 0 0 0 24 0 6 0 0 0 27
Guillermo Coria 0 9 0 5 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Andre Agassi 23 20 15 9 13 0 0 0 0 0 0 0 18 0 0 0 46 0 12 0
David Nalbandian 0 0 0 9 0 0 0 0 0 0 13 0 0 0 0 39 0 12 12 0
Gaston Gaudio 7 0 3 0 7 0 0 0 0 0 18 0 0 0 0 0 0 10 0 0
Guillermo Canas 0 7 0 8 0 0 0 0 14 24 0 11 0 0 0 0 25 0 0 0
Joachim Johansson 0 23 12 0 0 0 0 0 0 0 14 0 0 18 0 0 0 0 0 9
Tommy Robredo 0 9 5 0 0 0 0 12 0 0 0 0 0 0 0 0 0 0 0 0
Dominik Hrbaty 7 5 0 0 0 15 0 0 0 0 0 18 0 0 0 6 0 0 0 14
Sebastien Grosjean 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 15 0 0 0
Mikhail Youzhny 0 0 0 11 0 13 0 0 42 0 0 0 0 12 0 0 0 15 0 15
Tommy Haas 0 22 6 0 0 0 0 45 0 0 15 0 0 0 19 0 0 0 0 13
Nicolas Massu 0 0 3 0 13 0 0 0 7 13 0 0 0 0 0 12 0 0 13 0
Vince Spadea 0 0 0 0 0 0 0 4 8 0 0 0 0 0 0 0 0 8 0 0
Nicolas Kiefer 0 21 0 19 14 18 0 0 0 0 0 13 0 17 0 10 10 0 0 0
96
The weights and ranks obtained using the general SL-model for this data was calculated as
before in Mathematica.
Y={{0,25,43,13,15,18,0,24,0,13,0,0,0,16,0,0,0,0,0,0},{12,0,5,34,0,14,13,18,0,0,18,24,18,12,0,0,31,0,0,37},{18,12,0,22,18,12,0,11,0,12,0,19,12,0,0,0,18,4,0,0},{9,31,21,0,0,13,12,13,18,0,13,0,0,0,0,14,0,0,0,17},{12,0,13,0,0,0,0,9,0,12,0,0,0,0,0,0,0,7,0,14},{11,11,5,8,0,0,12,0,0,0,0,0,0,24,0,6,0,0,0,27},{0,9,0,5,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0},{23,20,15,9,13,0,0,0,0,0,0,0,18,0,0,0,46,0,12,0},{0,0,0,9,0,0,0,0,0,0,13,0,0,0,0,39,0,12,12,0},{7,0,3,0,7,0,0,0,0,0,18,0,0,0,0,0,0,10,0,0},{0,7,0,8,0,0,0,0,14,24,0,11,0,0,0,0,25,0,0,0},{0,23,12,0,0,0,0,0,0,0,14,0,0,18,0,0,0,0,0,9},{0,9,5,0,0,0,0,12,0,0,0,0,0,0,0,0,0,0,0,0},{7,5,0,0,0,15,0,0,0,0,0,18,0,0,0,6,0,0,0,14},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,0,0,0},{0,0,0,11,0,13,0,0,42,0,0,0,0,12,0,0,0,15,0,15},{0,22,6,0,0,0,0,45,0,0,15,0,0,0,19,0,0,0,0,13},{0,0,3,0,13,0,0,0,7,13,0,0,0,0,0,12,0,0,13,0},{0,0,0,0,0,0,0,4,8,0,0,0,0,0,0,0,0,8,0,0},{0,21,0,19,14,18,0,0,0,0,0,13,0,17,0,10,10,0,0,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.5},{i,1,20}]]
{p[1]→0.865971,p[2]→0.668329,p[3]→0.729157,p[4]→0.702211,p[5]
→0.54826,p[6]→0.57944,p[7]→0.311334,p[8]→0.667698,p[9]→0.5716
52,p[10]→0.377549,p[11]→0.52114,p[12]→0.519568,p[13]→0.384071
,p[14]→0.404215,p[15]→0.38898,p[16]→0.670224,p[17]→0.506627,p
[18]→0.553494,p[19]→0.291035,p[20]→0.5}
97
The following results were obtained:
ATP Race
Standings For
11/22/04 Player Country
2nd half of
2004 SL-Model
Weight
2nd half of
2004 SL-
Model Rank
1 Federer, Roger SUI 0.865971 1
2 Roddick, Andy USA 0.668329 5
3 Hewitt, Lleyton AUS 0.729157 2
4 Safin, Marat RUS 0.702211 3
5 Moya, Carlos ESP 0.54826 10
6 Henman, Tim GBR 0.57944 7
7 Coria, Guillermo ARG 0.311334 19
8 Agassi, Andre USA 0.667698 6
9 Nalbandian, David ARG 0.571652 8
10 Gaudio, Gaston ARG 0.377549 18
11 Canas, Guillermo ARG 0.52114 11
12 Johansson, Joachim SWE 0.519568 12
13 Robredo, Tommy ESP 0.384071 17
14 Hrbaty, Dominik SVK 0.404215 15
15 Grosjean, Sebastien FRA 0.38898 16
16 Youzhny, Mikhail RUS 0.670224 4
17 Haas, Tommy GER 0.506627 13
18 Massu, Nicolas CHI 0.553494 9
19 Spadea, Vincent USA 0.291035 20
20 Kiefer, Nicolas GER 0.5 14
We then again went on to calculate Kendal's τ and Spearman's ρ and used them to test the
association between the general SL-model (using just 2nd half of 2004 data) ranks and the
official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2nd half o
f 2004 SL-
Model R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2nd half of 2004 SL-
Model Rank
1 5 2 3 10 7 19 6 8 18 11 12 17 15 16 4 13 9 20 14
Roger Federer 1 1
Andy Roddick 2 5 1
Lleyton Hewitt 3 2 1 –1
Marat Safin 4 3 1 –1 1
Carlos Moya 5 10 1 1 1 1
Tim Henman 6 7 1 1 1 1 –1
Guillermo Coria 7 19 1 1 1 1 1 1
Andre Agassi 8 6 1 1 1 1 –1 –1 –1
David Nalbandian 9 8 1 1 1 1 –1 1 –1 1
Gaston Gaudio 10 18 1 1 1 1 1 1 –1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 –1 1 1 –1
Joachim Johansson 12 12 1 1 1 1 1 1 –1 1 1 –1 1
Tommy Robredo 13 17 1 1 1 1 1 1 –1 1 1 –1 1 1
Dominik Hrbaty 14 15 1 1 1 1 1 1 –1 1 1 –1 1 1 –1
Sebastien Grosjean 15 16 1 1 1 1 1 1 –1 1 1 –1 1 1 –1 1
Mikhail Youzhny 16 4 1 –1 1 1 –1 –1 –1 –1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 13 1 1 1 1 1 1 –1 1 1 –1 1 1 –1 –1 –1 1
Nicolas Massu 18 9 1 1 1 1 –1 1 –1 1 1 –1 –1 –1 –1 –1 –1 1 –1
Vince Spadea 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 20 14 1 1 1 1 1 1 –1 1 1 –1 1 1 –1 –1 –1 1 1 1 –1
99
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.442105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 84
z = 2.72532
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the second half of 2004 data, and the
ATP ranks.
100
Player
ATP Race
Standings For
11/22/04
2nd half of
2004 SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 5 9
Hewitt, Lleyton 3 2 1
Safin, Marat 4 3 1
Moya, Carlos 5 10 25
Henman, Tim 6 7 1
Coria, Guillermo 7 19 144
Agassi, Andre 8 6 4
Nalbandian, David 9 8 1
Gaudio, Gaston 10 18 64
Canas, Guillermo 11 11 0
Johansson, Joachim 12 12 0
Robredo, Tommy 13 17 16
Hrbaty, Dominik 14 15 1
Grosjean, Sebastien 15 16 1
Youzhny, Mikhail 16 4 144
Haas, Tommy 17 13 16
Massu, Nicolas 18 9 81
Spadea, Vincent 19 20 1
Kiefer, Nicolas 20 14 36
Total 546
ρ = 0.589474
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.589474
101
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 2.569456
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model on the second half of 2004 data, and the
ATP ranks.
We thus found that the data from the first half of the year had a stronger association with the
official ranks than the data from the second half of the year, which is the opposite to what
should occur if the official ranks gave more weight to more recent tournaments, so we
concluded that that was not the reason why our measure of association was not higher.
7.4 Real Life Application of the Binary SL-Model
Even though the tests conclude that there is an association between the SL-model ranks and
the official ranks, the measures of association are not that good, especially for data from the
second half of the year. We then decided to simply use cumulative number of wins in our
model, instead of cumulative scores, as sometimes ranks of players are calculated in this
manner. We called this the binary SL-model (bin SL-model) as score is 1 if a team wins and
0 if it looses.
The data for 2004 for cumulative number of wins was thus summarised on the next page:
Cumulative number of
wins of ↓ when playing
against →
(2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 7 15 7 4 5 3 5 3 4 0 0 2 1 3 2 0 0 0 3
Andy Roddick 1 0 2 8 2 3 4 1 0 0 5 4 3 2 2 0 4 0 3 6
Lleyton Hewitt 2 2 0 2 6 4 0 1 0 4 0 3 2 0 0 0 5 1 0 0
Marat Safin 0 4 2 0 0 2 3 5 4 0 2 0 2 0 2 2 0 0 1 1
Carlos Moya 1 1 2 0 0 0 0 0 3 2 0 0 7 2 0 0 0 0 0 1
Tim Henman 2 2 0 0 0 0 3 0 0 0 2 0 2 3 0 0 0 2 2 3
Guillermo Coria 1 1 0 2 5 3 0 0 2 2 0 0 2 0 2 1 0 0 0 6
Andre Agassi 3 2 2 2 2 0 2 0 0 0 0 0 2 2 2 2 5 0 2 0
David Nalbandian 1 0 0 3 0 0 0 0 0 0 4 0 0 2 0 3 0 2 4 0
Gaston Gaudio 1 0 4 0 2 0 3 0 3 0 5 0 5 0 0 0 0 0 0 0
Guillermo Canas 0 2 0 0 0 3 0 0 2 7 0 0 1 0 0 0 6 0 0 0
Joachim Johansson 0 3 0 0 0 0 0 0 0 0 2 0 0 1 0 0 0 0 0 4
Tommy Robredo 0 0 0 1 0 0 0 1 0 3 2 0 0 0 0 0 0 3 0 0
Dominik Hrbaty 2 0 0 0 1 1 0 0 0 3 0 2 0 0 1 0 0 0 0 1
Sebastien Grosjean 0 0 0 0 0 0 1 0 0 0 0 0 0 3 0 3 1 0 0 0
Mikhail Youzhny 0 0 0 0 0 2 2 0 5 0 0 0 0 4 0 0 0 2 0 4
Tommy Haas 0 1 0 0 0 0 0 3 0 0 0 0 0 0 3 0 0 0 1 2
Nicolas Massu 0 0 0 2 2 1 0 0 0 2 0 0 0 0 0 1 0 0 2 0
Vince Spadea 0 2 0 2 0 1 0 0 0 0 0 0 0 0 0 0 2 0 0 2
Nicolas Kiefer 0 0 0 2 2 2 0 0 0 0 0 3 0 2 2 2 0 0 1 0
103
From the cumulative number of wins for 2004 the weights and ranks obtained using the SL-
model for this data was calculated as before in Mathematica.
Y={{0,7,15,7,4,5,3,5,3,4,0,0,2,1,3,2,0,0,0,3},{1,0,2,8,2,3,4,1,0,0,5,4,3,2,2,0,4,0,3,6},{2,2,0,2,6,4,0,1,0,4,0,3,2,0,0,0,5,1,0,0},{0,4,2,0,0,2,3,5,4,0,2,0,2,0,2,2,0,0,1,1},{1,1,2,0,0,0,0,0,3,2,0,0,7,2,0,0,0,0,0,1},{2,2,0,0,0,0,3,0,0,0,2,0,2,3,0,0,0,2,2,3},{1,1,0,2,5,3,0,0,2,2,0,0,2,0,2,1,0,0,0,6},{3,2,2,2,2,0,2,0,0,0,0,0,2,2,2,2,5,0,2,0},{1,0,0,3,0,0,0,0,0,0,4,0,0,2,0,3,0,2,4,0},{1,0,4,0,2,0,3,0,3,0,5,0,5,0,0,0,0,0,0,0},{0,2,0,0,0,3,0,0,2,7,0,0,1,0,0,0,6,0,0,0},{0,3,0,0,0,0,0,0,0,0,2,0,0,1,0,0,0,0,0,4},{0,0,0,1,0,0,0,1,0,3,2,0,0,0,0,0,0,3,0,0},{2,0,0,0,1,1,0,0,0,3,0,2,0,0,1,0,0,0,0,1},{0,0,0,0,0,0,1,0,0,0,0,0,0,3,0,3,1,0,0,0},{0,0,0,0,0,2,2,0,5,0,0,0,0,4,0,0,0,2,0,4},{0,1,0,0,0,0,0,3,0,0,0,0,0,0,3,0,0,0,1,2},{0,0,0,2,2,1,0,0,0,2,0,0,0,0,0,1,0,0,2,0},{0,2,0,2,0,1,0,0,0,0,0,0,0,0,0,0,2,0,0,2},{0,0,0,2,2,2,0,0,0,0,0,3,0,2,2,2,0,0,1,0}} y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.0541},{i,1,20}]]
{p[1]→1.11731,p[2]→0.760563,p[3]→0.712574,p[4]→0.516633,p[5]→
0.365933,p[6]→0.426267,p[7]→0.596503,p[8]→0.730478,p[9]→0.417
469,p[10]→0.395205,p[11]→0.372021,p[12]→0.340322,p[13]→0.0000
678147,p[14]→0.293066,p[15]→0.0495587,p[16]→0.428695,p[17]→0.
115443,p[18]→0.327698,p[19]→0.181146,p[20]→0.0541}
104
The following results were obtained:
ATP Race
Standings For
11/22/04 Player Country
2004 Bin SL-
Model Weight
2004 Bin SL-
Model Rank
1 Federer, Roger SUI 1.11731 1
2 Roddick, Andy USA 0.760563 2
3 Hewitt, Lleyton AUS 0.712574 4
4 Safin, Marat RUS 0.516633 6
5 Moya, Carlos ESP 0.365933 12
6 Henman, Tim GBR 0.426267 8
7 Coria, Guillermo ARG 0.596503 5
8 Agassi, Andre USA 0.730478 3
9 Nalbandian, David ARG 0.417469 9
10 Gaudio, Gaston ARG 0.395205 10
11 Canas, Guillermo ARG 0.372021 11
12 Johansson, Joachim SWE 0.340322 13
13 Robredo, Tommy ESP 6.7815E-05 20
14 Hrbaty, Dominik SVK 0.293066 15
15 Grosjean, Sebastien FRA 0.0495587 19
16 Youzhny, Mikhail RUS 0.428695 7
17 Haas, Tommy GER 0.115443 17
18 Massu, Nicolas CHI 0.327698 14
19 Spadea, Vincent USA 0.181146 16
20 Kiefer, Nicolas GER 0.0541 18
We then again went on to calculate Kendal's τ and Spearman's ρ and used them to test the
association between the binary SL-model ranks and the official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2004 Bin SL-M
odel
Rank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2004 Bin SL-Model
Rank
1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 3 4 1 1
Marat Safin 4 6 1 1 1
Carlos Moya 5 12 1 1 1 1
Tim Henman 6 8 1 1 1 1 –1
Guillermo Coria 7 5 1 1 1 –1 –1 –1
Andre Agassi 8 3 1 1 –1 –1 –1 –1 –1
David Nalbandian 9 9 1 1 1 1 –1 1 1 1
Gaston Gaudio 10 10 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 1
Joachim Johansson 12 13 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 13 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 15 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 16 7 1 1 1 1 –1 –1 1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Massu 18 14 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1
Vince Spadea 19 16 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 –1 1
Nicolas Kiefer 20 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 1 1
106
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.64210526
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 122
z = 3.95820268
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the 2004 data, and the ATP ranks.
107
Player
ATP Race
Standings For
11/22/04
2004 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 3 4 1
Safin, Marat 4 6 4
Moya, Carlos 5 12 49
Henman, Tim 6 8 4
Coria, Guillermo 7 5 4
Agassi, Andre 8 3 25
Nalbandian, David 9 9 0
Gaudio, Gaston 10 10 0
Canas, Guillermo 11 11 0
Johansson, Joachim 12 13 1
Robredo, Tommy 13 20 49
Hrbaty, Dominik 14 15 1
Grosjean, Sebastien 15 19 16
Youzhny, Mikhail 16 7 81
Haas, Tommy 17 17 0
Massu, Nicolas 18 14 16
Spadea, Vincent 19 16 9
Kiefer, Nicolas 20 18 4
Total 264
ρ = 0.801504
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.801504
108
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.493674
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the 2004 data, and the ATP ranks.
We however noticed that these measures of association using cumulative number of wins is
slightly less than that using cumulative scores. We also found that the weights of the objects
were not all between 0 and 1, as required by theorem 4 to get proper probabilities. This could
be because the data contains too many zeros in it.
We then proceeded to do the same analysis on the cumulative number of wins from the first
half of the year and the cumulative number of wins from the second half of the year.
Cumulative number of
wins of ↓ when playing
against →
(first half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 3 8 5 2 2 3 2 3 2 0 0 2 0 3 2 0 0 0 3
Andy Roddick 1 0 2 4 2 1 2 0 0 0 2 2 0 0 2 0 0 0 3 0
Lleyton Hewitt 2 0 0 0 4 2 0 0 0 2 0 0 0 0 0 0 2 0 0 0
Marat Safin 0 3 0 0 0 0 1 3 1 0 0 0 2 0 2 0 0 0 1 0
Carlos Moya 0 1 1 0 0 0 0 0 3 0 0 0 7 2 0 0 0 0 0 0
Tim Henman 2 2 0 0 0 0 1 0 0 0 2 0 2 0 0 0 0 2 2 0
Guillermo Coria 1 1 0 2 5 3 0 0 2 2 0 0 2 0 2 1 0 0 0 6
Andre Agassi 1 0 0 2 0 0 2 0 0 0 0 0 0 2 2 2 0 0 0 0
David Nalbandian 1 0 0 3 0 0 0 0 0 0 3 0 0 2 0 0 0 0 2 0
Gaston Gaudio 1 0 4 0 2 0 3 0 3 0 3 0 5 0 0 0 0 0 0 0
Guillermo Canas 0 2 0 0 0 3 0 0 0 4 0 0 1 0 0 0 2 0 0 0
Joachim Johansson 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4
Tommy Robredo 0 0 0 1 0 0 0 0 0 3 2 0 0 0 0 0 0 3 0 0
Dominik Hrbaty 0 0 0 0 1 0 0 0 0 3 0 0 0 0 1 0 0 0 0 0
Sebastien Grosjean 0 0 0 0 0 0 1 0 0 0 0 0 0 3 0 3 0 0 0 0
Mikhail Youzhny 0 0 0 0 0 0 2 0 0 0 0 0 0 2 0 0 0 0 0 2
Tommy Haas 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Nicolas Massu 0 0 0 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Vince Spadea 0 2 0 2 0 1 0 0 0 0 0 0 0 0 0 0 2 0 0 2
Nicolas Kiefer 0 0 0 0 0 0 0 0 0 0 0 1 0 0 2 1 0 0 1 0
Cumulative number of
wins of ↓ when playing
against →
(second half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 4 7 2 2 3 0 3 0 2 0 0 0 1 0 0 0 0 0 0
Andy Roddick 0 0 0 4 0 2 2 1 0 0 3 2 3 2 0 0 4 0 0 6
Lleyton Hewitt 0 2 0 2 2 2 0 1 0 2 0 3 2 0 0 0 3 1 0 0
Marat Safin 0 1 2 0 0 2 2 2 3 0 2 0 0 0 0 2 0 0 0 1
Carlos Moya 1 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 1
Tim Henman 0 0 0 0 0 0 2 0 0 0 0 0 0 3 0 0 0 0 0 3
Guillermo Coria 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Andre Agassi 2 2 2 0 2 0 0 0 0 0 0 0 2 0 0 0 5 0 2 0
David Nalbandian 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 3 0 2 2 0
Gaston Gaudio 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0
Guillermo Canas 0 0 0 0 0 0 0 0 2 3 0 0 0 0 0 0 4 0 0 0
Joachim Johansson 0 3 0 0 0 0 0 0 0 0 2 0 0 1 0 0 0 0 0 0
Tommy Robredo 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
Dominik Hrbaty 2 0 0 0 0 1 0 0 0 0 0 2 0 0 0 0 0 0 0 1
Sebastien Grosjean 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0
Mikhail Youzhny 0 0 0 0 0 2 0 0 5 0 0 0 0 2 0 0 0 2 0 2
Tommy Haas 0 1 0 0 0 0 0 3 0 0 0 0 0 0 3 0 0 0 0 2
Nicolas Massu 0 0 0 0 2 0 0 0 0 2 0 0 0 0 0 1 0 0 2 0
Vince Spadea 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Nicolas Kiefer 0 0 0 2 2 2 0 0 0 0 0 2 0 2 0 1 0 0 0 0
111
The weights and ranks obtained using the SL-model on cumulative number of wins (i.e.
Binary SL-Model) for the data from the first half of 2004 and that of the second half of 2004
respectively was calculated as before in Mathematica.
Y={{0,3,8,5,2,2,3,2,3,2,0,0,2,0,3,2,0,0,0,3},{1,0,2,4,2,1,2,0,
0,0,2,2,0,0,2,0,0,0,3,0},{2,0,0,0,4,2,0,0,0,2,0,0,0,0,0,0,2,0,
0,0},{0,3,0,0,0,0,1,3,1,0,0,0,2,0,2,0,0,0,1,0},{0,1,1,0,0,0,0,
0,3,0,0,0,7,2,0,0,0,0,0,0},{2,2,0,0,0,0,1,0,0,0,2,0,2,0,0,0,0,
2,2,0},{1,1,0,2,5,3,0,0,2,2,0,0,2,0,2,1,0,0,0,6},{1,0,0,2,0,0,
2,0,0,0,0,0,0,2,2,2,0,0,0,0},{1,0,0,3,0,0,0,0,0,0,3,0,0,2,0,0,
0,0,2,0},{1,0,4,0,2,0,3,0,3,0,3,0,5,0,0,0,0,0,0,0},{0,2,0,0,0,
3,0,0,0,4,0,0,1,0,0,0,2,0,0,0},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,4},{0,0,0,1,0,0,0,0,0,3,2,0,0,0,0,0,0,3,0,0},{0,0,0,0,
1,0,0,0,0,3,0,0,0,0,1,0,0,0,0,0},{0,0,0,0,0,0,1,0,0,0,0,0,0,3,
0,3,0,0,0,0},{0,0,0,0,0,0,2,0,0,0,0,0,0,2,0,0,0,0,0,2},{0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0},{0,0,0,2,0,1,0,0,0,0,0,0,0,
0,0,0,0,0,0,0},{0,2,0,2,0,1,0,0,0,0,0,0,0,0,0,0,2,0,0,2},{0,0,
0,0,0,0,0,0,0,0,0,1,0,0,2,1,0,0,1,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}]
FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.1047},{i,1,20}]]
{p[1]→1.76777,p[2]→1.20716,p[3]→1.17902,p[4]→0.876676,p[5]→0.
922572,p[6]→1.14342,p[7]→1.22699,p[8]→1.40502,p[9]→1.07541,p[
10]→1.08755,p[11]→0.988795,p[12]→0.507545,p[13]→0.577857,p[14
]→0.555997,p[15]→0.495449,p[16]→0.624965,p[17]→0.0000645822,p
[18]→0.648951,p[19]→0.679012,p[20]→0.1047}
112
Y={{0,4,7,2,2,3,0,3,0,2,0,0,0,1,0,0,0,0,0,0},{0,0,0,4,0,2,2,1,
0,0,3,2,3,2,0,0,4,0,0,6},{0,2,0,2,2,2,0,1,0,2,0,3,2,0,0,0,3,1,
0,0},{0,1,2,0,0,2,2,2,3,0,2,0,0,0,0,2,0,0,0,1},{1,0,1,0,0,0,0,
0,0,2,0,0,0,0,0,0,0,0,0,1},{0,0,0,0,0,0,2,0,0,0,0,0,0,3,0,0,0,
0,0,3},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},{2,2,2,0,2,0,
0,0,0,0,0,0,2,0,0,0,5,0,2,0},{0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,3,
0,2,2,0},{0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0},{0,0,0,0,0,
0,0,0,2,3,0,0,0,0,0,0,4,0,0,0},{0,3,0,0,0,0,0,0,0,0,2,0,0,1,0,
0,0,0,0,0},{0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0},{2,0,0,0,
0,1,0,0,0,0,0,2,0,0,0,0,0,0,0,1},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,1,0,0,0},{0,0,0,0,0,2,0,0,5,0,0,0,0,2,0,0,0,2,0,2},{0,1,0,
0,0,0,0,3,0,0,0,0,0,0,3,0,0,0,0,2},{0,0,0,0,2,0,0,0,0,2,0,0,0,
0,0,1,0,0,2,0},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},{0,0,
0,2,2,2,0,0,0,0,0,2,0,2,0,1,0,0,0,0}}
y[i_,j_]:=Extract[Y,{i,j}]
l[i_,j_]:=y[i,j]/(p[i]+1-p[j])
r[i_,j_]:=l[j,i]
s[i_,j_]:=l[i,j]-r[i,j]
e[i_]:=Sum[s[i,j],{j,1,20}]
FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.5},{i,1,20}]]
8p@1D → 1.36237, p@2D → 1.07141, p@3D → 1.13472, p@4D → 1.02549,
p@5D → 0.594295, p@6D → 0.274676, p@7D → −9.2152×106, p@8D → 0.860383,
p@9D → 0.397084, p@10D → −0.512893, p@11D → 0.104891, p@12D → 0.628258,
p@13D → 0.130653, p@14D → 0.618676, p@15D → −0.163415, p@16D → 0.811015,
p@17D → 0.336585, p@18D → 0.531816, p@19D → −9.25924×106, p@20D → 0.5<
113
The following results were obtained:
ATP Race
Standings
For
11/22/04 Player Country
1st half of
2004 Bin
SL-Model
Weight
1st half of
2004 Bin
SL-Model
Rank
2nd half of
2004 Bin SL-
Model
Weight
2nd half of
2004 Bin
SL-Model
Rank
1 Federer, Roger SUI 1.76777 1 1.36237 1
2 Roddick, Andy USA 1.20716 4 1.07141 3
3 Hewitt, Lleyton AUS 1.17902 5 1.13472 2
4 Safin, Marat RUS 0.876676 11 1.02549 4
5 Moya, Carlos ESP 0.922572 10 0.594295 9
6 Henman, Tim GBR 1.14342 6 0.274676 14
7 Coria, Guillermo ARG 1.22699 3 –9215199 19
8 Agassi, Andre USA 1.40502 2 0.860383 5
9 Nalbandian, David ARG 1.07541 8 0.397084 12
10 Gaudio, Gaston ARG 1.08755 7 –0.512893 18
11 Canas, Guillermo ARG 0.988795 9 0.104891 16
12 Johansson, Joachim SWE 0.507545 17 0.628258 7
13 Robredo, Tommy ESP 0.577857 15 0.130653 15
14 Hrbaty, Dominik SVK 0.555997 16 0.618676 8
15 Grosjean, Sebastien FRA 0.495449 18 –0.163415 17
16 Youzhny, Mikhail RUS 0.624965 14 0.811015 6
17 Haas, Tommy GER 6.4582E-05 20 0.336585 13
18 Massu, Nicolas CHI 0.648951 13 0.531816 10
19 Spadea, Vincent USA 0.679012 12 –9259244 20
20 Kiefer, Nicolas GER 0.1047 19 0.5 11
We then again went on to calculate Kendal's τ and Spearman's ρ and used them to test the
association between the binary SL-model ranks for the first half of the year and the official
ranks, and the association between the binary SL-model ranks for the second half of the year
and the official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
1st h
alf of 2
004 Bin SL-
Model R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1st half of 2004 Bin
SL-Model Rank
1 4 5 11 10 6 3 2 8 7 9 17 15 16 18 14 20 13 12 19
Roger Federer 1 1
Andy Roddick 2 4 1
Lleyton Hewitt 3 5 1 1
Marat Safin 4 11 1 1 1
Carlos Moya 5 10 1 1 1 –1
Tim Henman 6 6 1 1 1 –1 –1
Guillermo Coria 7 3 1 –1 –1 –1 –1 –1
Andre Agassi 8 2 1 –1 –1 –1 –1 –1 –1
David Nalbandian 9 8 1 1 1 –1 –1 1 1 1
Gaston Gaudio 10 7 1 1 1 –1 –1 1 1 1 –1
Guillermo Canas 11 9 1 1 1 –1 –1 1 1 1 1 1
Joachim Johansson 12 17 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 13 15 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 14 16 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 15 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 16 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 18 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1 –1 –1
Vince Spadea 19 12 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1 –1 –1 –1
Nicolas Kiefer 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
115
(1st half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.56842105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 108
z = 3.5039827
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the first half of 2004 data, and the
ATP ranks.
116
Player
ATP Race
Standings For
11/22/04
1st half of
2004 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 4 4
Hewitt, Lleyton 3 5 4
Safin, Marat 4 11 49
Moya, Carlos 5 10 25
Henman, Tim 6 6 0
Coria, Guillermo 7 3 16
Agassi, Andre 8 2 36
Nalbandian, David 9 8 1
Gaudio, Gaston 10 7 9
Canas, Guillermo 11 9 4
Johansson, Joachim 12 17 25
Robredo, Tommy 13 15 4
Hrbaty, Dominik 14 16 4
Grosjean, Sebastien 15 18 9
Youzhny, Mikhail 16 14 4
Haas, Tommy 17 20 9
Massu, Nicolas 18 13 25
Spadea, Vincent 19 12 49
Kiefer, Nicolas 20 19 1
Total 278
ρ = 0.790977
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.790977
117
(1st half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.447791
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the first half of 2004 data, and the
ATP ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2nd half o
f 2004 Bin SL-
Model R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2nd half of 2004 Bin
SL-Model Rank
1 3 2 4 9 14 19 5 12 18 16 7 15 8 17 6 13 10 20 11
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 3 2 1 –1
Marat Safin 4 4 1 1 1
Carlos Moya 5 9 1 1 1 1
Tim Henman 6 14 1 1 1 1 1
Guillermo Coria 7 19 1 1 1 1 1 1
Andre Agassi 8 5 1 1 1 1 –1 –1 –1
David Nalbandian 9 12 1 1 1 1 1 –1 –1 1
Gaston Gaudio 10 18 1 1 1 1 1 1 –1 1 1
Guillermo Canas 11 16 1 1 1 1 1 1 –1 1 1 –1
Joachim Johansson 12 7 1 1 1 1 –1 –1 –1 1 –1 –1 –1
Tommy Robredo 13 15 1 1 1 1 1 1 –1 1 1 –1 –1 1
Dominik Hrbaty 14 8 1 1 1 1 –1 –1 –1 1 –1 –1 –1 1 –1
Sebastien Grosjean 15 17 1 1 1 1 1 1 –1 1 1 –1 1 1 1 1
Mikhail Youzhny 16 6 1 1 1 1 –1 –1 –1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 13 1 1 1 1 1 –1 –1 1 1 –1 –1 1 –1 1 –1 1
Nicolas Massu 18 10 1 1 1 1 1 –1 –1 1 –1 –1 –1 1 –1 1 –1 1 –1
Vince Spadea 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 20 11 1 1 1 1 1 –1 –1 1 –1 –1 –1 1 –1 1 –1 1 –1 1 –1
119
(2nd half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.36842105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 70
z = 2.2710999
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the second half of 2004 data, and the
ATP ranks.
120
Player
ATP Race
Standings For
11/22/04
2nd half of
2004 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 3 2 1
Safin, Marat 4 4 0
Moya, Carlos 5 9 16
Henman, Tim 6 14 64
Coria, Guillermo 7 19 144
Agassi, Andre 8 5 9
Nalbandian, David 9 12 9
Gaudio, Gaston 10 18 64
Canas, Guillermo 11 16 25
Johansson, Joachim 12 7 25
Robredo, Tommy 13 15 4
Hrbaty, Dominik 14 8 36
Grosjean, Sebastien 15 17 4
Youzhny, Mikhail 16 6 100
Haas, Tommy 17 13 16
Massu, Nicolas 18 10 64
Spadea, Vincent 19 20 1
Kiefer, Nicolas 20 11 81
Total 664
ρ = 0.500752
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.500752
121
(2nd half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 2.182727
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model on the second half of 2004 data, and the
ATP ranks.
As with the data for the whole year, we noticed that these measures of association using
cumulative number of wins for the 1st half and for the 2nd half of 2004 is slightly less than
that using cumulative scores for the 1st half and for the 2
nd half of 2004. We also again found
that the weights of the objects were not between 0 and 1, as required by theorem 4 to get
proper probabilities. This could be because the data contains too many zeros in it.
7.5 Real Life Application of the DDic01 Binary SL-Model
We then went on to try an approach to achieve weights which yield proper probabilities. The
approach is as follows: we double the values in the data, and change the zeros to ones in
cases where objects were compared. We will call this approach the doubled data if compared
zeros become ones binary SL-model (DDic01 Bin SL-Model).
The cumulative number of wins for 2004 doubled, and zeros made ones if relevant objects
were compared was thus summarised on the next page:
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones if
relevant objects were
compared. (2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 14 30 14 8 10 6 10 6 8 0 0 4 2 6 4 0 0 0 6
Andy Roddick 2 0 4 16 4 6 8 2 0 0 10 8 6 4 4 0 8 0 6 12
Lleyton Hewitt 4 4 0 4 12 8 0 2 0 8 0 6 4 0 0 0 10 2 0 0
Marat Safin 1 8 4 0 0 4 6 10 8 0 4 0 4 0 4 4 0 1 2 2
Carlos Moya 2 2 4 0 0 0 1 1 6 4 0 0 14 4 0 0 0 1 0 2
Tim Henman 4 4 1 1 0 0 6 0 0 0 4 0 4 6 0 1 0 4 4 6
Guillermo Coria 2 2 0 4 10 6 0 1 4 4 0 0 4 0 4 2 0 0 0 12
Andre Agassi 6 4 4 4 4 0 4 0 0 0 0 0 4 4 4 4 10 0 4 0
David Nalbandian 2 0 0 6 1 0 1 0 0 1 8 0 0 4 0 6 0 4 8 0
Gaston Gaudio 2 0 8 0 4 0 6 0 6 0 10 0 10 1 0 0 0 1 0 0
Guillermo Canas 0 4 0 1 0 6 0 0 4 14 0 1 2 0 0 0 12 0 0 0
Joachim Johansson 0 6 1 0 0 0 0 0 0 0 4 0 0 2 0 0 0 0 0 8
Tommy Robredo 1 1 1 2 1 1 1 2 0 6 4 0 0 0 0 0 0 6 0 0
Dominik Hrbaty 4 1 0 0 2 2 0 1 1 6 0 4 0 0 2 1 0 0 0 2
Sebastien Grosjean 1 1 0 1 0 0 2 1 0 0 0 0 0 6 0 6 2 0 0 1
Mikhail Youzhny 1 0 0 1 0 4 4 1 10 0 0 0 0 8 1 0 0 4 0 8
Tommy Haas 0 2 1 0 0 0 0 6 0 0 1 0 0 0 6 0 0 0 2 4
Nicolas Massu 0 0 1 4 4 2 0 0 1 4 0 0 1 0 0 2 0 0 4 0
Vince Spadea 0 4 0 4 0 2 0 1 1 0 0 0 0 0 0 0 4 1 0 4
Nicolas Kiefer 1 1 0 4 4 4 1 0 0 0 0 6 0 4 4 4 1 0 2 0
123
From the cumulative number of wins for 2004 doubled, and zeros made ones if relevant
objects were compared, the weights and ranks obtained using the SL-model for this data was
calculated as before in Mathematica.
Y={{0,14,30,14,8,10,6,10,6,8,0,0,4,2,6,4,0,0,0,6},{2,0,4,16,4,6,8,2,0,0,10,8,6,4,4,0,8,0,6,12},{4,4,0,4,12,8,0,2,0,8,0,6,4,0,0,0,10,2,0,0},{1,8,4,0,0,4,6,10,8,0,4,0,4,0,4,4,0,1,2,2},{2,2,4,0,0,0,1,1,6,4,0,0,14,4,0,0,0,1,0,2},{4,4,1,1,0,0,6,0,0,0,4,0,4,6,0,1,0,4,4,6},{2,2,0,4,10,6,0,1,4,4,0,0,4,0,4,2,0,0,0,12},{6,4,4,4,4,0,4,0,0,0,0,0,4,4,4,4,10,0,4,0},{2,0,0,6,1,0,1,0,0,1,8,0,0,4,0,6,0,4,8,0},{2,0,8,0,4,0,6,0,6,0,10,0,10,1,0,0,0,1,0,0},{0,4,0,1,0,6,0,0,4,14,0,1,2,0,0,0,12,0,0,0},{0,6,1,0,0,0,0,0,0,0,4,0,0,2,0,0,0,0,0,8},{1,1,1,2,1,1,1,2,0,6,4,0,0,0,0,0,0,6,0,0},{4,1,0,0,2,2,0,1,1,6,0,4,0,0,2,1,0,0,0,2},{1,1,0,1,0,0,2,1,0,0,0,0,0,6,0,6,2,0,0,1},{1,0,0,1,0,4,4,1,10,0,0,0,0,8,1,0,0,4,0,8},{0,2,1,0,0,0,0,6,0,0,1,0,0,0,6,0,0,0,2,4},{0,0,1,4,4,2,0,0,1,4,0,0,1,0,0,2,0,0,4,0},{0,4,0,4,0,2,0,1,1,0,0,0,0,0,0,0,4,1,0,4},{1,1,0,4,4,4,1,0,0,0,0,6,0,4,4,4,1,0,2,0}} y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.1},{i,1,20}]]
{p[1]→0.93816,p[2]→0.632797,p[3]→0.523808,p[4]→0.424977,p[5]→
0.275565,p[6]→0.34456,p[7]→0.480285,p[8]→0.58117,p[9]→0.33209
2,p[10]→0.311781,p[11]→0.310053,p[12]→0.280915,p[13]→0.081430
1,p[14]→0.211087,p[15]→0.173209,p[16]→0.437442,p[17]→0.049335
5,p[18]→0.280334,p[19]→0.165194,p[20]→0.1}
124
The following results were obtained:
ATP Race
Standings For
11/22/04 Player Country
2004 DDic01
Bin SL-Model
Weight
2004 DDic01
Bin SL-Model
Rank
1 Federer, Roger SUI 0.93816 1
2 Roddick, Andy USA 0.632797 2
3 Hewitt, Lleyton AUS 0.523808 4
4 Safin, Marat RUS 0.424977 7
5 Moya, Carlos ESP 0.275565 14
6 Henman, Tim GBR 0.34456 8
7 Coria, Guillermo ARG 0.480285 5
8 Agassi, Andre USA 0.58117 3
9 Nalbandian, David ARG 0.332092 9
10 Gaudio, Gaston ARG 0.311781 10
11 Canas, Guillermo ARG 0.310053 11
12 Johansson, Joachim SWE 0.280915 12
13 Robredo, Tommy ESP 0.08143 19
14 Hrbaty, Dominik SVK 0.211087 15
15 Grosjean, Sebastien FRA 0.173209 16
16 Youzhny, Mikhail RUS 0.437442 6
17 Haas, Tommy GER 0.049336 20
18 Massu, Nicolas CHI 0.280334 13
19 Spadea, Vincent USA 0.165194 17
20 Kiefer, Nicolas GER 0.1 18
We noted that all the weights of the objects are between zero and one, which yields proper
probabilities.
We then calculated Kendal's τ and Spearman's ρ and used them to test the association
between the doubled data if compared zeros become ones binary SL-model ranks and the
official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2004 DDic0
1 Bin SL-
Model R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2004 DDic01 Bin SL-
Model Rank
1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 3 4 1 1
Marat Safin 4 7 1 1 1
Carlos Moya 5 14 1 1 1 1
Tim Henman 6 8 1 1 1 1 –1
Guillermo Coria 7 5 1 1 1 –1 –1 –1
Andre Agassi 8 3 1 1 –1 –1 –1 –1 –1
David Nalbandian 9 9 1 1 1 1 –1 1 1 1
Gaston Gaudio 10 10 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 1
Joachim Johansson 12 12 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 13 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 15 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 16 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 16 6 1 1 1 –1 –1 –1 1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 18 13 1 1 1 1 –1 1 1 1 1 1 1 1 –1 –1 –1 1 –1
Vince Spadea 19 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1
Nicolas Kiefer 20 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1 1
126
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.64210526
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 122
z = 3.95820268
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the 2004 data, and the ATP
ranks.
127
Player
ATP Race
Standings For
11/22/04
2004 DDic01
Bin SL-Model
Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 3 4 1
Safin, Marat 4 7 9
Moya, Carlos 5 14 81
Henman, Tim 6 8 4
Coria, Guillermo 7 5 4
Agassi, Andre 8 3 25
Nalbandian, David 9 9 0
Gaudio, Gaston 10 10 0
Canas, Guillermo 11 11 0
Johansson, Joachim 12 12 0
Robredo, Tommy 13 19 36
Hrbaty, Dominik 14 15 1
Grosjean, Sebastien 15 16 1
Youzhny, Mikhail 16 6 100
Haas, Tommy 17 20 9
Massu, Nicolas 18 13 25
Spadea, Vincent 19 17 4
Kiefer, Nicolas 20 18 4
Total 304
ρ = 0.771429
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.771429
128
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.362579
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the 2004 data, and the ATP
ranks.
We noticed the value of τ remained the same as that of the bin SL-model, but the value of ρ
decreased slightly.
We then proceeded to do the same analysis on the cumulative number of wins for the first
half of 2004, and then on the cumulative number of wins for the second half of 2004, both
doubled, with zeros made ones if relevant objects were compared.
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones if
relevant objects were
compared.
(first half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 6 16 10 4 4 6 4 6 4 0 0 4 0 6 4 0 0 0 6
Andy Roddick 2 0 4 8 4 2 4 0 0 0 4 4 0 0 4 0 0 0 6 0
Lleyton Hewitt 4 1 0 0 8 4 0 0 0 4 0 0 0 0 0 0 4 0 0 0
Marat Safin 1 6 0 0 0 0 2 6 2 0 0 0 4 0 4 0 0 1 2 0
Carlos Moya 1 2 2 0 0 0 1 0 6 1 0 0 14 4 0 0 0 0 0 0
Tim Henman 4 4 1 0 0 0 2 0 0 0 4 0 4 0 0 0 0 4 4 0
Guillermo Coria 2 2 0 4 10 6 0 1 4 4 0 0 4 0 4 2 0 0 0 12
Andre Agassi 2 0 0 4 0 0 4 0 0 0 0 0 0 4 4 4 0 0 0 0
David Nalbandian 2 0 0 6 1 0 1 0 0 1 6 0 0 4 0 0 0 0 4 0
Gaston Gaudio 2 0 8 0 4 0 6 0 6 0 6 0 10 1 0 0 0 0 0 0
Guillermo Canas 0 4 0 0 0 6 0 0 1 8 0 0 2 0 0 0 4 0 0 0
Joachim Johansson 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8
Tommy Robredo 1 0 0 2 1 1 1 0 0 6 4 0 0 0 0 0 0 6 0 0
Dominik Hrbaty 0 0 0 0 2 0 0 1 1 6 0 0 0 0 2 1 0 0 0 0
Sebastien Grosjean 1 1 0 1 0 0 2 1 0 0 0 0 0 6 0 6 0 0 0 1
Mikhail Youzhny 1 0 0 0 0 0 4 1 0 0 0 0 0 4 1 0 0 0 0 4
Tommy Haas 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 2 0
Nicolas Massu 0 0 0 4 0 2 0 0 0 0 0 0 1 0 0 0 0 0 0 0
Vince Spadea 0 4 0 4 0 2 0 0 1 0 0 0 0 0 0 0 4 0 0 4
Nicolas Kiefer 1 0 0 0 0 0 1 0 0 0 0 2 0 0 4 2 0 0 2 0
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones if
relevant objects were
compared.
(second half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 8 14 4 4 6 0 6 0 4 0 0 0 2 0 0 0 0 0 0
Andy Roddick 1 0 1 8 0 4 4 2 0 0 6 4 6 4 0 0 8 0 0 12
Lleyton Hewitt 1 4 0 4 4 4 0 2 0 4 0 6 4 0 0 0 6 2 0 0
Marat Safin 1 2 4 0 0 4 4 4 6 0 4 0 0 0 0 4 0 0 0 2
Carlos Moya 2 0 2 0 0 0 0 1 0 4 0 0 0 0 0 0 0 1 0 2
Tim Henman 1 1 1 1 0 0 4 0 0 0 0 0 0 6 0 1 0 0 0 6
Guillermo Coria 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Andre Agassi 4 4 4 1 4 0 0 0 0 0 0 0 4 0 0 0 10 0 4 0
David Nalbandian 0 0 0 1 0 0 0 0 0 0 2 0 0 0 0 6 0 4 4 0
Gaston Gaudio 1 0 1 0 1 0 0 0 0 0 4 0 0 0 0 0 0 1 0 0
Guillermo Canas 0 1 0 1 0 0 0 0 4 6 0 1 0 0 0 0 8 0 0 0
Joachim Johansson 0 6 1 0 0 0 0 0 0 0 4 0 0 2 0 0 0 0 0 1
Tommy Robredo 0 1 1 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0
Dominik Hrbaty 4 1 0 0 0 2 0 0 0 0 0 4 0 0 0 1 0 0 0 2
Sebastien Grosjean 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0
Mikhail Youzhny 0 0 0 1 0 4 0 0 10 0 0 0 0 4 0 0 0 4 0 4
Tommy Haas 0 2 1 0 0 0 0 6 0 0 1 0 0 0 6 0 0 0 0 4
Nicolas Massu 0 0 1 0 4 0 0 0 1 4 0 0 0 0 0 2 0 0 4 0
Vince Spadea 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 1 0 0
Nicolas Kiefer 0 1 0 4 4 4 0 0 0 0 0 4 0 4 0 2 1 0 0 0
131
The weights and ranks obtained using the SL-model on cumulative number of wins for the
first half, and then the second half of 2004 doubled, both with zeros made ones if relevant
objects were compared, was calculated as before in Mathematica.
Y={{0,6,16,10,4,4,6,4,6,4,0,0,4,0,6,4,0,0,0,6},{2,0,4,8,4,2,4,0,0,0,4,4,0,0,4,0,0,0,6,0},{4,1,0,0,8,4,0,0,0,4,0,0,0,0,0,0,4,0,0,0},{1,6,0,0,0,0,2,6,2,0,0,0,4,0,4,0,0,1,2,0},{1,2,2,0,0,0,1,0,6,1,0,0,14,4,0,0,0,0,0,0},{4,4,1,0,0,0,2,0,0,0,4,0,4,0,0,0,0,4,4,0},{2,2,0,4,10,6,0,1,4,4,0,0,4,0,4,2,0,0,0,12},{2,0,0,4,0,0,4,0,0,0,0,0,0,4,4,4,0,0,0,0},{2,0,0,6,1,0,1,0,0,1,6,0,0,4,0,0,0,0,4,0},{2,0,8,0,4,0,6,0,6,0,6,0,10,1,0,0,0,0,0,0},{0,4,0,0,0,6,0,0,1,8,0,0,2,0,0,0,4,0,0,0},{0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,8},{1,0,0,2,1,1,1,0,0,6,4,0,0,0,0,0,0,6,0,0},{0,0,0,0,2,0,0,1,1,6,0,0,0,0,2,1,0,0,0,0},{1,1,0,1,0,0,2,1,0,0,0,0,0,6,0,6,0,0,0,1},{1,0,0,0,0,0,4,1,0,0,0,0,0,4,1,0,0,0,0,4},{0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,2,0},{0,0,0,4,0,2,0,0,0,0,0,0,1,0,0,0,0,0,0,0},{0,4,0,4,0,2,0,0,1,0,0,0,0,0,0,0,4,0,0,4},{1,0,0,0,0,0,1,0,0,0,0,2,0,0,4,2,0,0,2,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.1871},{i,1,20}]]
{p[1]→1.05449,p[2]→0.724642,p[3]→0.579425,p[4]→0.426525,p[5]→
0.523942,p[6]→0.61904,p[7]→0.793071,p[8]→0.773148,p[9]→0.5632
61,p[10]→0.64124,p[11]→0.531046,p[12]→0.588809,p[13]→0.273285
,p[14]→0.283213,p[15]→0.367626,p[16]→0.453802,p[17]→0.0000792
924,p[18]→0.221942,p[19]→0.420679,p[20]→0.1871}
132
Y={{0,8,14,4,4,6,0,6,0,4,0,0,0,2,0,0,0,0,0,0},{1,0,1,8,0,4,4,2,0,0,6,4,6,4,0,0,8,0,0,12},{1,4,0,4,4,4,0,2,0,4,0,6,4,0,0,0,6,2,0,0},{1,2,4,0,0,4,4,4,6,0,4,0,0,0,0,4,0,0,0,2},{2,0,2,0,0,0,0,1,0,4,0,0,0,0,0,0,0,1,0,2},{1,1,1,1,0,0,4,0,0,0,0,0,0,6,0,1,0,0,0,6},{0,1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0},{4,4,4,1,4,0,0,0,0,0,0,0,4,0,0,0,10,0,4,0},{0,0,0,1,0,0,0,0,0,0,2,0,0,0,0,6,0,4,4,0},{1,0,1,0,1,0,0,0,0,0,4,0,0,0,0,0,0,1,0,0},{0,1,0,1,0,0,0,0,4,6,0,1,0,0,0,0,8,0,0,0},{0,6,1,0,0,0,0,0,0,0,4,0,0,2,0,0,0,0,0,1},{0,1,1,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0},{4,1,0,0,0,2,0,0,0,0,0,4,0,0,0,1,0,0,0,2},{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0},{0,0,0,1,0,4,0,0,10,0,0,0,0,4,0,0,0,4,0,4},{0,2,1,0,0,0,0,6,0,0,1,0,0,0,6,0,0,0,0,4},{0,0,1,0,4,0,0,0,1,4,0,0,0,0,0,2,0,0,4,0},{0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,1,0,0},{0,1,0,4,4,4,0,0,0,0,0,4,0,4,0,2,1,0,0,0}} y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.6878},{i,1,20}]]
{p[1]→1.43377,p[2]→1.09411,p[3]→0.970572,p[4]→1.01853,p[5]→0.
673684,p[6]→0.745264,p[7]→0.384997,p[8]→0.96273,p[9]→0.680493
,p[10]→0.157362,p[11]→0.604093,p[12]→0.746786,p[13]→0.452895,
p[14]→0.808295,p[15]→0.0000354485,p[16]→1.00653,p[17]→0.50003
5,p[18]→0.718357,p[19]→0.221106,p[20]→0.6878}
133
The following results were obtained:
ATP Race
Standings
For
11/22/04 Player Country
1st half of
2004 DDic01
Bin SL-Model
Weight
1st half of
2004 DDic01
Bin SL-
Model Rank
2nd half of
2004 DDic01
Bin SL-
Model
Weight
2nd half of
2004
DDic01 Bin
SL-Model
Rank
1 Federer, Roger SUI 1.05449 1 1.43377 1
2 Roddick, Andy USA 0.724642 4 1.09411 2
3 Hewitt, Lleyton AUS 0.579425 8 0.970572 5
4 Safin, Marat RUS 0.426525 13 1.01853 3
5 Moya, Carlos ESP 0.523942 11 0.673684 13
6 Henman, Tim GBR 0.61904 6 0.745264 9
7 Coria, Guillermo ARG 0.793071 2 0.384997 17
8 Agassi, Andre USA 0.773148 3 0.96273 6
9 Nalbandian, David ARG 0.563261 9 0.680493 12
10 Gaudio, Gaston ARG 0.64124 5 0.157362 19
11 Canas, Guillermo ARG 0.531046 10 0.604093 14
12 Johansson, Joachim SWE 0.588809 7 0.746786 8
13 Robredo, Tommy ESP 0.273285 17 0.452895 16
14 Hrbaty, Dominik SVK 0.283213 16 0.808295 7
15 Grosjean, Sebastien FRA 0.367626 15 3.545E-05 20
16 Youzhny, Mikhail RUS 0.453802 12 1.00653 4
17 Haas, Tommy GER 7.929E-05 20 0.500035 15
18 Massu, Nicolas CHI 0.221942 18 0.718357 10
19 Spadea, Vincent USA 0.420679 14 0.221106 18
20 Kiefer, Nicolas GER 0.1871 19 0.6878 11
Kendal's τ and Spearman's ρ and the tests for association between the DDic01 bin SL-model
ranks and the official ranks follow as:
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
1st h
alf of 2
004 DDic0
1
Bin SL-M
odel R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1st half of 2004 DDic01
Bin SL-Model Rank
1 4 8 13 11 6 2 3 9 5 10 7 17 16 15 12 20 18 14 19
Roger Federer 1 1
Andy Roddick 2 4 1
Lleyton Hewitt 3 8 1 1
Marat Safin 4 13 1 1 1
Carlos Moya 5 11 1 1 1 –1
Tim Henman 6 6 1 1 –1 –1 –1
Guillermo Coria 7 2 1 –1 –1 –1 –1 –1
Andre Agassi 8 3 1 –1 –1 –1 –1 –1 1
David Nalbandian 9 9 1 1 1 –1 –1 1 1 1
Gaston Gaudio 10 5 1 1 –1 –1 –1 –1 1 1 –1
Guillermo Canas 11 10 1 1 1 –1 –1 1 1 1 1 1
Joachim Johansson 12 7 1 1 –1 –1 –1 1 1 1 –1 1 –1
Tommy Robredo 13 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 16 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 16 12 1 1 1 –1 1 1 1 1 1 1 1 1 –1 –1 –1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 18 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Vince Spadea 19 14 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 –1
Nicolas Kiefer 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
135
(1st half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.55789474
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 106
z = 3.43909413
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the first half of 2004 data,
and the ATP ranks.
136
Player
ATP Race
Standings For
11/22/04
1st half of 2004
DDic01 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 4 4
Hewitt, Lleyton 3 8 25
Safin, Marat 4 13 81
Moya, Carlos 5 11 36
Henman, Tim 6 6 0
Coria, Guillermo 7 2 25
Agassi, Andre 8 3 25
Nalbandian, David 9 9 0
Gaudio, Gaston 10 5 25
Canas, Guillermo 11 10 1
Johansson, Joachim 12 7 25
Robredo, Tommy 13 17 16
Hrbaty, Dominik 14 16 4
Grosjean, Sebastien 15 15 0
Youzhny, Mikhail 16 12 16
Haas, Tommy 17 20 9
Massu, Nicolas 18 18 0
Spadea, Vincent 19 14 25
Kiefer, Nicolas 20 19 1
Total 318
ρ = 0.760902
nn
d6
13
n
1i
2
i
−−=ρ∑= =0.760902
137
(1st half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.316696
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the first half of 2004 data,
and the ATP ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2nd half o
f 2004 DDic0
1 Bin
SL-M
odel R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2nd half of 2004 DDic01
Bin SL-Model Rank
1 2 5 3 13 9 17 6 12 19 14 8 16 7 20 4 15 10 18 11
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 3 5 1 1
Marat Safin 4 3 1 1 –1
Carlos Moya 5 13 1 1 1 1
Tim Henman 6 9 1 1 1 1 –1
Guillermo Coria 7 17 1 1 1 1 1 1
Andre Agassi 8 6 1 1 1 1 –1 –1 –1
David Nalbandian 9 12 1 1 1 1 –1 1 –1 1
Gaston Gaudio 10 19 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 14 1 1 1 1 1 1 –1 1 1 –1
Joachim Johansson 12 8 1 1 1 1 –1 –1 –1 1 –1 –1 –1
Tommy Robredo 13 16 1 1 1 1 1 1 –1 1 1 –1 1 1
Dominik Hrbaty 14 7 1 1 1 1 –1 –1 –1 1 –1 –1 –1 –1 –1
Sebastien Grosjean 15 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 16 4 1 1 –1 1 –1 –1 –1 –1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 15 1 1 1 1 1 1 –1 1 1 –1 1 1 –1 1 –1 1
Nicolas Massu 18 10 1 1 1 1 –1 1 –1 1 –1 –1 –1 1 –1 1 –1 1 –1
Vince Spadea 19 18 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 –1 1 1 1
Nicolas Kiefer 20 11 1 1 1 1 –1 1 –1 1 –1 –1 –1 1 –1 1 –1 1 –1 1 –1
139
(2nd half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.36842105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 70
z = 2.2710999
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the second half of 2004 data,
and the ATP ranks.
140
Player
ATP Race
Standings For
11/22/04
2nd half of 2004
DDic01 Bin SL-
Model Rank
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 3 5 4
Safin, Marat 4 3 1
Moya, Carlos 5 13 64
Henman, Tim 6 9 9
Coria, Guillermo 7 17 100
Agassi, Andre 8 6 4
Nalbandian, David 9 12 9
Gaudio, Gaston 10 19 81
Canas, Guillermo 11 14 9
Johansson, Joachim 12 8 16
Robredo, Tommy 13 16 9
Hrbaty, Dominik 14 7 49
Grosjean, Sebastien 15 20 25
Youzhny, Mikhail 16 4 144
Haas, Tommy 17 15 4
Massu, Nicolas 18 10 64
Spadea, Vincent 19 18 1
Kiefer, Nicolas 20 11 81
Total 674
ρ = 0.493233
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.493233
141
(2nd half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 2.149953
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model on the second half of 2004 data,
and the ATP ranks.
We noticed that the value of τ and ρ is less than that of the bin SL-model for the data from
the first half of the year. As with the data for the whole year, we noticed the value of τ for the
data of the second half of the year remained the same as that of the bin SL-model, but the
value of ρ decreased slightly for the data of the second half of the year. Unlike the data for
the whole year, we found that the weights of the objects were not between 0 and 1, as
required by theorem 4 to get proper probabilities. This could be because the data contains too
many zeros in it.
7.6 Real Life Application of the DD01 Binary SL-Model
We then went on to try another approach to achieve weights which yield proper probabilities.
The approach is as follows: we double the values in the data, and change the zeros to ones
(even if objects were not compared). We will call this approach the doubled data zeros
become ones binary SL-model (DD01 bin SL-model).
The cumulative number of wins for 2004 doubled, and zeros made ones thus summarised on
the next page:
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones.
(2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 14 30 14 8 10 6 10 6 8 1 1 4 2 6 4 1 1 1 6
Andy Roddick 2 0 4 16 4 6 8 2 1 1 10 8 6 4 4 1 8 1 6 12
Lleyton Hewitt 4 4 0 4 12 8 1 2 1 8 1 6 4 1 1 1 10 2 1 1
Marat Safin 1 8 4 0 1 4 6 10 8 1 4 1 4 1 4 4 1 1 2 2
Carlos Moya 2 2 4 1 0 1 1 1 6 4 1 1 14 4 1 1 1 1 1 2
Tim Henman 4 4 1 1 1 0 6 1 1 1 4 1 4 6 1 1 1 4 4 6
Guillermo Coria 2 2 1 4 10 6 0 1 4 4 1 1 4 1 4 2 1 1 1 12
Andre Agassi 6 4 4 4 4 1 4 0 1 1 1 1 4 4 4 4 10 1 4 1
David Nalbandian 2 1 1 6 1 1 1 1 0 1 8 1 1 4 1 6 1 4 8 1
Gaston Gaudio 2 1 8 1 4 1 6 1 6 0 10 1 10 1 1 1 1 1 1 1
Guillermo Canas 1 4 1 1 1 6 1 1 4 14 0 1 2 1 1 1 12 1 1 1
Joachim Johansson 1 6 1 1 1 1 1 1 1 1 4 0 1 2 1 1 1 1 1 8
Tommy Robredo 1 1 1 2 1 1 1 2 1 6 4 1 0 1 1 1 1 6 1 1
Dominik Hrbaty 4 1 1 1 2 2 1 1 1 6 1 4 1 0 2 1 1 1 1 2
Sebastien Grosjean 1 1 1 1 1 1 2 1 1 1 1 1 1 6 0 6 2 1 1 1
Mikhail Youzhny 1 1 1 1 1 4 4 1 10 1 1 1 1 8 1 0 1 4 1 8
Tommy Haas 1 2 1 1 1 1 1 6 1 1 1 1 1 1 6 1 0 1 2 4
Nicolas Massu 1 1 1 4 4 2 1 1 1 4 1 1 1 1 1 2 1 0 4 1
Vince Spadea 1 4 1 4 1 2 1 1 1 1 1 1 1 1 1 1 4 1 0 4
Nicolas Kiefer 1 1 1 4 4 4 1 1 1 1 1 6 1 4 4 4 1 1 2 0
143
From the cumulative number of wins for 2004 doubled, and zeros made ones, the weights
and ranks obtained using the SL-model for this data was calculated as before in Mathematica
Y={{0,14,30,14,8,10,6,10,6,8,1,1,4,2,6,4,1,1,1,6},{2,0,4,16,4,
6,8,2,1,1,10,8,6,4,4,1,8,1,6,12},{4,4,0,4,12,8,1,2,1,8,1,6,4,1
,1,1,10,2,1,1},{1,8,4,0,1,4,6,10,8,1,4,1,4,1,4,4,1,1,2,2},{2,2
,4,1,0,1,1,1,6,4,1,1,14,4,1,1,1,1,1,2},{4,4,1,1,1,0,6,1,1,1,4,
1,4,6,1,1,1,4,4,6},{2,2,1,4,10,6,0,1,4,4,1,1,4,1,4,2,1,1,1,12}
,{6,4,4,4,4,1,4,0,1,1,1,1,4,4,4,4,10,1,4,1},{2,1,1,6,1,1,1,1,0
,1,8,1,1,4,1,6,1,4,8,1},{2,1,8,1,4,1,6,1,6,0,10,1,10,1,1,1,1,1
,1,1},{1,4,1,1,1,6,1,1,4,14,0,1,2,1,1,1,12,1,1,1},{1,6,1,1,1,1
,1,1,1,1,4,0,1,2,1,1,1,1,1,8},{1,1,1,2,1,1,1,2,1,6,4,1,0,1,1,1
,1,6,1,1},{4,1,1,1,2,2,1,1,1,6,1,4,1,0,2,1,1,1,1,2},{1,1,1,1,1
,1,2,1,1,1,1,1,1,6,0,6,2,1,1,1},{1,1,1,1,1,4,4,1,10,1,1,1,1,8,
1,0,1,4,1,8},{1,2,1,1,1,1,1,6,1,1,1,1,1,1,6,1,0,1,2,4},{1,1,1,
4,4,2,1,1,1,4,1,1,1,1,1,2,1,0,4,1},{1,4,1,4,1,2,1,1,1,1,1,1,1,
1,1,1,4,1,0,4},{1,1,1,4,4,4,1,1,1,1,1,6,1,4,4,4,1,1,2,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.1},{i,1,20}]]
{p[1]→0.872914,p[2]→0.606218,p[3]→0.464433,p[4]→0.385799,p[5]
→0.243954,p[6]→0.310318,p[7]→0.425883,p[8]→0.53486,p[9]→0.303
993,p[10]→0.286521,p[11]→0.312851,p[12]→0.293871,p[13]→0.0653
021,p[14]→0.186385,p[15]→0.175566,p[16]→0.390476,p[17]→0.1227
26,p[18]→0.29549,p[19]→0.215774,p[20]→0.1}
144
The following results were obtained:
ATP Race
Standings For
11/22/04 Player Country
2004 DD01 Bin
SL-Model
Weight
2004 DD01 Bin
SL-Model Rank
1 Federer, Roger SUI 0.87291 1
2 Roddick, Andy USA 0.60622 2
3 Hewitt, Lleyton AUS 0.46443 4
4 Safin, Marat RUS 0.3858 7
5 Moya, Carlos ESP 0.24395 14
6 Henman, Tim GBR 0.31032 9
7 Coria, Guillermo ARG 0.42588 5
8 Agassi, Andre USA 0.53486 3
9 Nalbandian, David ARG 0.30399 10
10 Gaudio, Gaston ARG 0.28652 13
11 Canas, Guillermo ARG 0.31285 8
12 Johansson, Joachim SWE 0.29387 12
13 Robredo, Tommy ESP 0.0653 20
14 Hrbaty, Dominik SVK 0.18639 16
15 Grosjean, Sebastien FRA 0.17557 17
16 Youzhny, Mikhail RUS 0.39048 6
17 Haas, Tommy GER 0.12273 18
18 Massu, Nicolas CHI 0.29549 11
19 Spadea, Vincent USA 0.21577 15
20 Kiefer, Nicolas GER 0.1 19
We noted that all the weights of the objects are between zero and one, which yields proper
probabilities.
We then calculated Kendal's τ and Spearman's ρ and used them to test the association
between the DD01 binary SL-model ranks and the official ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2004 DD01 Bin SL-M
odel
Rank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2004 DD01 Bin SL-
Model Rank
1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 3 4 1 1
Marat Safin 4 7 1 1 1
Carlos Moya 5 14 1 1 1 1
Tim Henman 6 9 1 1 1 1 –1
Guillermo Coria 7 5 1 1 1 –1 –1 –1
Andre Agassi 8 3 1 1 –1 –1 –1 –1 –1
David Nalbandian 9 10 1 1 1 1 –1 1 1 1
Gaston Gaudio 10 13 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 –1
Joachim Johansson 12 12 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 13 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 16 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 16 6 1 1 1 –1 –1 –1 1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Massu 18 11 1 1 1 1 –1 1 1 1 1 –1 1 –1 –1 –1 –1 1 –1
Vince Spadea 19 15 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 1
Nicolas Kiefer 20 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 1
146
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.55789474
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 106
z = 3.43909413
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the 2004 data, and the ATP
ranks.
147
Player
ATP Race
Standings For
11/22/04
2004 DD01 Bin
SL-Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 3 4 1
Safin, Marat 4 7 9
Moya, Carlos 5 14 81
Henman, Tim 6 9 9
Coria, Guillermo 7 5 4
Agassi, Andre 8 3 25
Nalbandian, David 9 10 1
Gaudio, Gaston 10 13 9
Canas, Guillermo 11 8 9
Johansson, Joachim 12 12 0
Robredo, Tommy 13 20 49
Hrbaty, Dominik 14 16 4
Grosjean, Sebastien 15 17 4
Youzhny, Mikhail 16 6 100
Haas, Tommy 17 18 1
Massu, Nicolas 18 11 49
Spadea, Vincent 19 15 16
Kiefer, Nicolas 20 19 1
Total 372
ρ = 0.720301
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.720301
148
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.139718
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the 2004 data, and the ATP
ranks.
We noticed the value of τ and ρ decreased to that of the DDic01 bin SL-model. We then
proceeded to do the same analysis on the cumulative number of wins for the first half, and
then the second half of 2004 doubled, with zeros made ones.
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones.
(first half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 6 16 10 4 4 6 4 6 4 1 1 4 1 6 4 1 1 1 6
Andy Roddick 2 0 4 8 4 2 4 1 1 1 4 4 1 1 4 1 1 1 6 1
Lleyton Hewitt 4 1 0 1 8 4 1 1 1 4 1 1 1 1 1 1 4 1 1 1
Marat Safin 1 6 1 0 1 1 2 6 2 1 1 1 4 1 4 1 1 1 2 1
Carlos Moya 1 2 2 1 0 1 1 1 6 1 1 1 14 4 1 1 1 1 1 1
Tim Henman 4 4 1 1 1 0 2 1 1 1 4 1 4 1 1 1 1 4 4 1
Guillermo Coria 2 2 1 4 10 6 0 1 4 4 1 1 4 1 4 2 1 1 1 12
Andre Agassi 2 1 1 4 1 1 4 0 1 1 1 1 1 4 4 4 1 1 1 1
David Nalbandian 2 1 1 6 1 1 1 1 0 1 6 1 1 4 1 1 1 1 4 1
Gaston Gaudio 2 1 8 1 4 1 6 1 6 0 6 1 10 1 1 1 1 1 1 1
Guillermo Canas 1 4 1 1 1 6 1 1 1 8 0 1 2 1 1 1 4 1 1 1
Joachim Johansson 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 8
Tommy Robredo 1 1 1 2 1 1 1 1 1 6 4 1 0 1 1 1 1 6 1 1
Dominik Hrbaty 1 1 1 1 2 1 1 1 1 6 1 1 1 0 2 1 1 1 1 1
Sebastien Grosjean 1 1 1 1 1 1 2 1 1 1 1 1 1 6 0 6 1 1 1 1
Mikhail Youzhny 1 1 1 1 1 1 4 1 1 1 1 1 1 4 1 0 1 1 1 4
Tommy Haas 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 2 1
Nicolas Massu 1 1 1 4 1 2 1 1 1 1 1 1 1 1 1 1 1 0 1 1
Vince Spadea 1 4 1 4 1 2 1 1 1 1 1 1 1 1 1 1 4 1 0 4
Nicolas Kiefer 1 1 1 1 1 1 1 1 1 1 1 2 1 1 4 2 1 1 2 0
Cumulative number of
wins of ↓ when playing
against →, doubled,
and zeros made ones.
(second half of 2004)
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Roger Federer 0 8 14 4 4 6 1 6 1 4 1 1 1 2 1 1 1 1 1 1
Andy Roddick 1 0 1 8 1 4 4 2 1 1 6 4 6 4 1 1 8 1 1 12
Lleyton Hewitt 1 4 0 4 4 4 1 2 1 4 1 6 4 1 1 1 6 2 1 1
Marat Safin 1 2 4 0 1 4 4 4 6 1 4 1 1 1 1 4 1 1 1 2
Carlos Moya 2 1 2 1 0 1 1 1 1 4 1 1 1 1 1 1 1 1 1 2
Tim Henman 1 1 1 1 1 0 4 1 1 1 1 1 1 6 1 1 1 1 1 6
Guillermo Coria 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1
Andre Agassi 4 4 4 1 4 1 1 0 1 1 1 1 4 1 1 1 10 1 4 1
David Nalbandian 1 1 1 1 1 1 1 1 0 1 2 1 1 1 1 6 1 4 4 1
Gaston Gaudio 1 1 1 1 1 1 1 1 1 0 4 1 1 1 1 1 1 1 1 1
Guillermo Canas 1 1 1 1 1 1 1 1 4 6 0 1 1 1 1 1 8 1 1 1
Joachim Johansson 1 6 1 1 1 1 1 1 1 1 4 0 1 2 1 1 1 1 1 1
Tommy Robredo 1 1 1 1 1 1 1 2 1 1 1 1 0 1 1 1 1 1 1 1
Dominik Hrbaty 4 1 1 1 1 2 1 1 1 1 1 4 1 0 1 1 1 1 1 2
Sebastien Grosjean 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 2 1 1 1
Mikhail Youzhny 1 1 1 1 1 4 1 1 10 1 1 1 1 4 1 0 1 4 1 4
Tommy Haas 1 2 1 1 1 1 1 6 1 1 1 1 1 1 6 1 0 1 1 4
Nicolas Massu 1 1 1 1 4 1 1 1 1 4 1 1 1 1 1 2 1 0 4 1
Vince Spadea 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1
Nicolas Kiefer 1 1 1 4 4 4 1 1 1 1 1 4 1 4 1 2 1 1 1 0
151
The weights and ranks obtained using the SL-model on cumulative number of wins for the
first half, and then the second half of 2004 doubled, both with zeros made ones, was
calculated as before in Mathematica.
Y={{0,6,16,10,4,4,6,4,6,4,1,1,4,1,6,4,1,1,1,6},{2,0,4,8,4,2,4,1,1,1,4,4,1,1,4,1,1,1,6,1},{4,1,0,1,8,4,1,1,1,4,1,1,1,1,1,1,4,1,1,1},{1,6,1,0,1,1,2,6,2,1,1,1,4,1,4,1,1,1,2,1},{1,2,2,1,0,1,1,1,6,1,1,1,14,4,1,1,1,1,1,1},{4,4,1,1,1,0,2,1,1,1,4,1,4,1,1,1,1,4,4,1},{2,2,1,4,10,6,0,1,4,4,1,1,4,1,4,2,1,1,1,12},{2,1,1,4,1,1,4,0,1,1,1,1,1,4,4,4,1,1,1,1},{2,1,1,6,1,1,1,1,0,1,6,1,1,4,1,1,1,1,4,1},{2,1,8,1,4,1,6,1,6,0,6,1,10,1,1,1,1,1,1,1},{1,4,1,1,1,6,1,1,1,8,0,1,2,1,1,1,4,1,1,1},{1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1,8},{1,1,1,2,1,1,1,1,1,6,4,1,0,1,1,1,1,6,1,1},{1,1,1,1,2,1,1,1,1,6,1,1,1,0,2,1,1,1,1,1},{1,1,1,1,1,1,2,1,1,1,1,1,1,6,0,6,1,1,1,1},{1,1,1,1,1,1,4,1,1,1,1,1,1,4,1,0,1,1,1,4},{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,2,1},{1,1,1,4,1,2,1,1,1,1,1,1,1,1,1,1,1,0,1,1},{1,4,1,4,1,2,1,1,1,1,1,1,1,1,1,1,4,1,0,4},{1,1,1,1,1,1,1,1,1,1,1,2,1,1,4,2,1,1,2,0}}
y[i_,j_]:=Extract[Y,{i,j}] l[i_,j_]:=y[i,j]/(p[i]+1-p[j]) r[i_,j_]:=l[j,i] s[i_,j_]:=l[i,j]-r[i,j] e[i_]:=Sum[s[i,j],{j,1,20}] FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.1},{i,1,20}]]
{p[1]→0.830376,p[2]→0.499501,p[3]→0.378744,p[4]→0.257235,p[5]
→0.336571,p[6]→0.418081,p[7]→0.573793,p[8]→0.494131,p[9]→0.36
8851,p[10]→0.44904,p[11]→0.377154,p[12]→0.395556,p[13]→0.1543
36,p[14]→0.219685,p[15]→0.237944,p[16]→0.307766,p[17]→0.21906
8,p[18]→0.272986,p[19]→0.341943,p[20]→0.1}
152
Y={{0,8,14,4,4,6,1,6,1,4,1,1,1,2,1,1,1,1,1,1},{1,0,1,8,1,4,4,2,1,1,6,4,6,4,1,1,8,1,1,12},{1,4,0,4,4,4,1,2,1,4,1,6,4,1,1,1,6,2,1,1},{1,2,4,0,1,4,4,4,6,1,4,1,1,1,1,4,1,1,1,2},{2,1,2,1,0,1,1,1,1,4,1,1,1,1,1,1,1,1,1,2},{1,1,1,1,1,0,4,1,1,1,1,1,1,6,1,1,1,1,1,6},{1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1},{4,4,4,1,4,1,1,0,1,1,1,1,4,1,1,1,10,1,4,1},{1,1,1,1,1,1,1,1,0,1,2,1,1,1,1,6,1,4,4,1},{1,1,1,1,1,1,1,1,1,0,4,1,1,1,1,1,1,1,1,1},{1,1,1,1,1,1,1,1,4,6,0,1,1,1,1,1,8,1,1,1},{1,6,1,1,1,1,1,1,1,1,4,0,1,2,1,1,1,1,1,1},{1,1,1,1,1,1,1,2,1,1,1,1,0,1,1,1,1,1,1,1},{4,1,1,1,1,2,1,1,1,1,1,4,1,0,1,1,1,1,1,2},{1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,2,1,1,1},{1,1,1,1,1,4,1,1,10,1,1,1,1,4,1,0,1,4,1,4},{1,2,1,1,1,1,1,6,1,1,1,1,1,1,6,1,0,1,1,4},{1,1,1,1,4,1,1,1,1,4,1,1,1,1,1,2,1,0,4,1},{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1},{1,1,1,4,4,4,1,1,1,1,1,4,1,4,1,2,1,1,1,0}}
y[i_,j_]:=Extract[Y,{i,j}]
l[i_,j_]:=y[i,j]/(p[i]+1-p[j])
r[i_,j_]:=l[j,i]
s[i_,j_]:=l[i,j]-r[i,j]
e[i_]:=Sum[s[i,j],{j,1,20}]
FindRoot[Table[e[i]�0,{i,1,20}],Table[{p[i],0.4},{i,1,20}]]
{p[1]→0.874381,p[2]→0.767283,p[3]→0.655512,p[4]→0.644122,p[5]
→0.376358,p[6]→0.400856,p[7]→0.332007,p[8]→0.645403,p[9]→0.45
1899,p[10]→0.281825,p[11]→0.473016,p[12]→0.456345,p[13]→0.342
818,p[14]→0.408891,p[15]→0.395257,p[16]→0.63159,p[17]→0.35717
7,p[18]→0.531138,p[19]→0.326858,p[20]→0.4}
153
The following results were obtained:
ATP Race
Standings
For
11/22/04 Player Country
1st half of
2004 DD01
Bin SL-Model
Weight
1st half of
2004
DD01 Bin
SL-Model
Rank
2nd half of
2004 DD01
Bin SL-
Model
Weight
2nd half of
2004 DD01
Bin SL-
Model Rank
1 Federer, Roger SUI 0.830376 1 0.874381 1
2 Roddick, Andy USA 0.499501 3 0.767283 2
3 Hewitt, Lleyton AUS 0.378744 8 0.655512 3
4 Safin, Marat RUS 0.257235 15 0.644122 5
5 Moya, Carlos ESP 0.336571 12 0.376358 15
6 Henman, Tim GBR 0.418081 6 0.400856 12
7 Coria, Guillermo ARG 0.573793 2 0.332007 18
8 Agassi, Andre USA 0.494131 4 0.645403 4
9 Nalbandian, David ARG 0.368851 10 0.451899 10
10 Gaudio, Gaston ARG 0.44904 5 0.281825 20
11 Canas, Guillermo ARG 0.377154 9 0.473016 8
12 Johansson, Joachim SWE 0.395556 7 0.456345 9
13 Robredo, Tommy ESP 0.154336 19 0.342818 17
14 Hrbaty, Dominik SVK 0.219685 17 0.408891 11
15 Grosjean, Sebastien FRA 0.237944 16 0.395257 14
16 Youzhny, Mikhail RUS 0.307766 13 0.63159 6
17 Haas, Tommy GER 0.219068 18 0.357177 16
18 Massu, Nicolas CHI 0.272986 14 0.531138 7
19 Spadea, Vincent USA 0.341943 11 0.326858 19
20 Kiefer, Nicolas GER 0.1 20 0.4 13
Kendal's τ and Spearman's ρ and the tests for association between the DD01 bin SL-model
ranks and the official ranks follow as:
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
1st h
alf of 2
004 DD01
Bin SL-M
odel R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1st half of 2004 DD01 Bin
SL-Model Rank
1 4 8 13 11 6 2 3 9 5 10 7 17 16 15 12 20 18 14 19
Roger Federer 1 1
Andy Roddick 2 4 1
Lleyton Hewitt 3 8 1 1
Marat Safin 4 13 1 1 1
Carlos Moya 5 11 1 1 1 –1
Tim Henman 6 6 1 1 –1 –1 –1
Guillermo Coria 7 2 1 –1 –1 –1 –1 –1
Andre Agassi 8 3 1 –1 –1 –1 –1 –1 1
David Nalbandian 9 9 1 1 1 –1 –1 1 1 1
Gaston Gaudio 10 5 1 1 –1 –1 –1 –1 1 1 –1
Guillermo Canas 11 10 1 1 1 –1 –1 1 1 1 1 1
Joachim Johansson 12 7 1 1 –1 –1 –1 1 1 1 –1 1 –1
Tommy Robredo 13 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 14 16 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 16 12 1 1 1 –1 1 1 1 1 1 1 1 1 –1 –1 –1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 18 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Vince Spadea 19 14 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 –1
Nicolas Kiefer 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
155
(1st half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.48421053
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 92
z = 2.98487415
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the first half of 2004 data, and
the ATP ranks.
156
Player
ATP Race
Standings For
11/22/04
1st half of 2004
DD01 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 3 8 25
Safin, Marat 4 15 121
Moya, Carlos 5 12 49
Henman, Tim 6 6 0
Coria, Guillermo 7 2 25
Agassi, Andre 8 4 16
Nalbandian, David 9 10 1
Gaudio, Gaston 10 5 25
Canas, Guillermo 11 9 4
Johansson, Joachim 12 7 25
Robredo, Tommy 13 19 36
Hrbaty, Dominik 14 17 9
Grosjean, Sebastien 15 16 1
Youzhny, Mikhail 16 13 9
Haas, Tommy 17 18 1
Massu, Nicolas 18 14 16
Spadea, Vincent 19 11 64
Kiefer, Nicolas 20 20 0
Total 428
ρ = 0.678195
nn
d6
13
n
1i
2
i
−−=ρ∑= =0.678195
157
(1st half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 2.956186
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the first half of 2004 data, and
the ATP ranks.
ija
1 for agreement and
–1 for disagreement
ATP Race S
tandings
2nd half o
f 2004 DD01
Bin SL-M
odel R
ank
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
ATP Race Standings 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2nd half of 2004 DD01 Bin
SL-Model Rank
1 2 3 5 15 12 18 4 10 20 8 9 17 11 14 6 16 7 19 13
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 3 3 1 1
Marat Safin 4 5 1 1 1
Carlos Moya 5 15 1 1 1 1
Tim Henman 6 12 1 1 1 1 –1
Guillermo Coria 7 18 1 1 1 1 1 1
Andre Agassi 8 4 1 1 1 –1 –1 –1 –1
David Nalbandian 9 10 1 1 1 1 –1 –1 –1 1
Gaston Gaudio 10 20 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 8 1 1 1 1 –1 –1 –1 1 –1 –1
Joachim Johansson 12 9 1 1 1 1 –1 –1 –1 1 –1 –1 1
Tommy Robredo 13 17 1 1 1 1 1 1 –1 1 1 –1 1 1
Dominik Hrbaty 14 11 1 1 1 1 –1 –1 –1 1 1 –1 1 1 –1
Sebastien Grosjean 15 14 1 1 1 1 –1 1 –1 1 1 –1 1 1 –1 1
Mikhail Youzhny 16 6 1 1 1 1 –1 –1 –1 1 –1 –1 –1 –1 –1 –1 –1
Tommy Haas 17 16 1 1 1 1 1 1 –1 1 1 –1 1 1 –1 1 1 1
Nicolas Massu 18 7 1 1 1 1 –1 –1 –1 1 –1 –1 –1 –1 –1 –1 –1 1 –1
Vince Spadea 19 19 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 1 1 1
Nicolas Kiefer 20 13 1 1 1 1 –1 1 –1 1 1 –1 1 1 –1 1 –1 1 –1 1 –1
159
(2nd half of 2004 data)
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.35789474
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 68
z = 2.20621133
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the second half of 2004 data,
and the ATP ranks.
160
Player
ATP Race
Standings For
11/22/04
2nd half of 2004
DD01 Bin SL-
Model Rank
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 3 3 0
Safin, Marat 4 5 1
Moya, Carlos 5 15 100
Henman, Tim 6 12 36
Coria, Guillermo 7 18 121
Agassi, Andre 8 4 16
Nalbandian, David 9 10 1
Gaudio, Gaston 10 20 100
Canas, Guillermo 11 8 9
Johansson, Joachim 12 9 9
Robredo, Tommy 13 17 16
Hrbaty, Dominik 14 11 9
Grosjean, Sebastien 15 14 1
Youzhny, Mikhail 16 6 100
Haas, Tommy 17 16 1
Massu, Nicolas 18 7 121
Spadea, Vincent 19 19 0
Kiefer, Nicolas 20 13 49
Total 690
ρ = 0.481203
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.481203
161
(2nd half of 2004 data)
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 2.097515
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model on the second half of 2004 data,
and the ATP ranks.
As with the data for the whole year, we notice that the value of τ and ρ is less than that of the
DDic01 bin SL-model for the data from the first half and the data from second half of the
year. Also, we again found that the weights of the objects were all between 0 and 1, as
required by theorem 4 to get proper probabilities.
7.7 Comparison to other models
We noted that the official rankings was also influenced by when the top twenty players
played against other players not in the top twenty, which was not accounted for in our
analysis. Another reason why our measures of association are not higher, is due to the
method in which the official ranks are calculated which include letting some tournaments e.g.
grand slams have higher influence on scores than other tournaments, choosing best 3 games
from a tournament etc. We thus decided to compare the outcomes of the data for the whole
162
year using the general SL-model, the binary SL-model, the DDic01 binary SL-model and the
DD01 binary SL-model with other models for paired comparisons. The following ranks and
weights using other paired comparisons models were found:
Binomial Poisson B
Binomial Poisson
ML
ATP Race
Standings
For
11/22/04 Player Weights Ranks Weights Ranks
1 Federer, Roger 26.32614266 1 3175.965753 1
2 Roddick, Andy 19.43864486 3 2364.231223 3
3 Hewitt, Lleyton 17.70928622 7 2241.683929 4
4 Safin, Marat 17.90373436 5 2160.475201 5
5 Moya, Carlos 14.97394555 10 1933.287714 10
6 Henman, Tim 16.3442535 8 2002.383475 8
7 Coria, Guillermo 18.26369708 4 2117.816824 6
8 Agassi, Andre 22.45360208 2 2522.044821 2
9 Nalbandian, David 16.1078778 9 1992.317874 9
10 Gaudio, Gaston 14.53347682 12 1831.445255 13
11 Canas, Guillermo 14.91253433 11 1895.537385 11
12 Johansson, Joachim 14.32924027 15 1838.86228 12
13 Robredo, Tommy 12.77321182 19 1604.142581 18
14 Hrbaty, Dominik 13.21575788 18 1563.963008 20
15 Grosjean, Sebastien 14.42765157 13 1762.81286 15
16 Youzhny, Mikhail 17.83837001 6 2043.757559 7
17 Haas, Tommy 14.34440777 14 1693.427461 16
18 Massu, Nicolas 14.05871733 16 1796.641759 14
19 Spadea, Vincent 12.19231423 20 1692.152007 17
20 Kiefer, Nicolas 13.26149865 17 1583.387812 19
163
Bradley-Terry
ATP Race
Standings
For
11/22/04 Player Weights Ranks
1 Federer, Roger 0.079728732 1
2 Roddick, Andy 0.059792187 3
3 Hewitt, Lleyton 0.056277387 4
4 Safin, Marat 0.054251129 5
5 Moya, Carlos 0.048648297 10
6 Henman, Tim 0.05012986 9
7 Coria, Guillermo 0.05308978 6
8 Agassi, Andre 0.063616728 2
9 Nalbandian, David 0.05035668 8
10 Gaudio, Gaston 0.046013062 12
11 Canas, Guillermo 0.047542589 11
12 Johansson, Joachim 0.045557702 13
13 Robredo, Tommy 0.040334221 18
14 Hrbaty, Dominik 0.039087149 20
15 Grosjean, Sebastien 0.044467638 15
16 Youzhny, Mikhail 0.051170951 7
17 Haas, Tommy 0.042956224 16
18 Massu, Nicolas 0.045112652 14
19 Spadea, Vincent 0.042319623 17
20 Kiefer, Nicolas 0.039547409 19
164
Poisson PoissonApprox
ATP Race
Standings
For 11/22/04
Player
Weights
Ranks
Weights
Ranks
1 Federer, Roger 5.16015047 1 2.970883013 1
2 Roddick, Andy 3.972404548 3 2.150868715 3
3 Hewitt, Lleyton 3.764006293 4 2.019767845 5
4 Safin, Marat 3.392777991 7 1.505072794 14
5 Moya, Carlos 3.024030193 11 1.65733358 11
6 Henman, Tim 3.003035721 12 1.619656812 12
7 Coria, Guillermo 3.737974584 6 2.016408647 6
8 Agassi, Andre 4.432616537 2 2.225986608 2
9 Nalbandian, David 3.27269897 8 1.800994954 9
10 Gaudio, Gaston 3.171682442 9 1.873489182 7
11 Canas, Guillermo 3.13945052 10 1.854520573 8
12 Johansson, Joachim 2.561499031 17 1.345287155 16
13 Robredo, Tommy 2.650759879 16 1.325780588 17
14 Hrbaty, Dominik 2.514576809 18 1.37174803 15
15 Grosjean, Sebastien 2.877863631 14 1.507239151 13
16 Youzhny, Mikhail 3.755308219 5 2.058324339 4
17 Haas, Tommy 2.717192249 15 1.189370168 18
18 Massu, Nicolas 2.959635214 13 1.669726009 10
19 Spadea, Vincent 2.009889636 20 1.127847091 19
20 Kiefer, Nicolas 2.13349056 19 0.970583865 20
165
RowSum
ATP Race
Standings
For
11/22/04 Player Weights Ranks
1 Federer, Roger 192 1
2 Roddick, Andy 150 2
3 Hewitt, Lleyton 96 3
4 Safin, Marat 90 4
5 Moya, Carlos 57 10
6 Henman, Tim 63 9
7 Coria, Guillermo 81 6
8 Agassi, Andre 84 5
9 Nalbandian, David 57 12
10 Gaudio, Gaston 69 7
11 Canas, Guillermo 63 8
12 Johansson, Joachim 30 16
13 Robredo, Tommy 30 18
14 Hrbaty, Dominik 33 14
15 Grosjean, Sebastien 24 20
16 Youzhny, Mikhail 57 11
17 Haas, Tommy 30 15
18 Massu, Nicolas 30 17
19 Spadea, Vincent 27 19
20 Kiefer, Nicolas 48 13
166
The ranks obtained for the various models are summarised below:
ATP Player
General S
L-M
odel
Bin SL-M
odel
DDic0
1 Bin SL-M
odel
DD01 Bin SL-M
odel
Binomial P
oisso
n B
Binomial P
oisso
n M
L
Brad
ley
Poisso
n
Poisso
n Approx
Row Sum
1 Federer, Roger 1 1 1 1 1 1 1 1 1 1
2 Roddick, Andy 3 2 2 2 3 3 3 3 3 2
3 Hewitt, Lleyton 4 4 4 4 7 4 4 4 5 3
4 Safin, Marat 5 6 7 7 5 5 5 7 14 4
5 Moya, Carlos 10 12 14 14 10 10 10 11 11 10
6 Henman, Tim 9 8 8 9 8 8 9 12 12 9
7 Coria, Guillermo 6 5 5 5 4 6 6 6 6 6
8 Agassi, Andre 2 3 3 3 2 2 2 2 2 5
9 Nalbandian, David 8 9 9 10 9 9 8 8 9 12
10 Gaudio, Gaston 12 10 10 13 12 13 12 9 7 7
11 Canas, Guillermo 11 11 11 8 11 11 11 10 8 8
12 Johansson, Joachim 14 13 12 12 15 12 13 17 16 16
13 Robredo, Tommy 18 20 19 20 19 18 18 16 17 18
14 Hrbaty, Dominik 20 15 15 16 18 20 20 18 15 14
15 Grosjean, Sebastien 15 19 16 17 13 15 15 14 13 20
16 Youzhny, Mikhail 7 7 6 6 6 7 7 5 4 11
17 Haas, Tommy 16 17 20 18 14 16 16 15 18 15
18 Massu, Nicolas 13 14 13 11 16 14 14 13 10 17
19 Spadea, Vincent 17 16 17 15 20 17 17 20 19 19
20 Kiefer, Nicolas 19 18 18 19 17 19 19 19 20 13
Kendal's τ, Spearman's ρ and the tests for association between the various ranks follow.
7.7.1 General SL-Model vs Binary SL-Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 6 1 1 1
Carlos Moya 10 12 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 6 5 1 1 1 –1 1 1
Andre Agassi 2 3 1 –1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 10 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 14 13 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 15 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 19 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
Nicolas Massu 13 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1
Nicolas Kiefer 19 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1 1
168
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.82105263
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 156
z = 5.06130834
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the binary SL-
model.
169
Player
General
SL-
Model
Bin
SL-
Model
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 4 0
Safin, Marat 5 6 1
Moya, Carlos 10 12 4
Henman, Tim 9 8 1
Coria, Guillermo 6 5 1
Agassi, Andre 2 3 1
Nalbandian, David 8 9 1
Gaudio, Gaston 12 10 4
Canas, Guillermo 11 11 0
Johansson, Joachim 14 13 1
Robredo, Tommy 18 20 4
Hrbaty, Dominik 20 15 25
Grosjean, Sebastien 15 19 16
Youzhny, Mikhail 7 7 0
Haas, Tommy 16 17 1
Massu, Nicolas 13 14 1
Spadea, Vincent 17 16 1
Kiefer, Nicolas 19 18 1
Total 64
ρ = 0.95188
170
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.95188
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.149147
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the binary SL-
model.
7.7.2 General SL-Model vs DDic01 Binary SL-Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
DDic0
1 Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 7 1 1 1
Carlos Moya 10 14 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 6 5 1 1 1 –1 1 1
Andre Agassi 2 3 1 –1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 10 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 14 12 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 18 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 15 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 7 6 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 13 13 1 1 1 1 –1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1
Nicolas Kiefer 19 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 –1 1 1
172
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.8
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 152
z = 4.9315312
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the DDic01
binary SL-model.
173
Player
General
SL-
Model
DDic01
Bin SL-
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 4 0
Safin, Marat 5 7 4
Moya, Carlos 10 14 16
Henman, Tim 9 8 1
Coria, Guillermo 6 5 1
Agassi, Andre 2 3 1
Nalbandian, David 8 9 1
Gaudio, Gaston 12 10 4
Canas, Guillermo 11 11 0
Johansson, Joachim 14 12 4
Robredo, Tommy 18 19 1
Hrbaty, Dominik 20 15 25
Grosjean, Sebastien 15 16 1
Youzhny, Mikhail 7 6 1
Haas, Tommy 16 20 16
Massu, Nicolas 13 13 0
Spadea, Vincent 17 17 0
Kiefer, Nicolas 19 18 1
Total 78
ρ = 0.941353
174
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.941353
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.103264
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the DDic01
binary SL-model.
7.7.3 General SL-Model vs DD01 Binary SL-Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
DD01 Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 7 1 1 1
Carlos Moya 10 14 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 6 5 1 1 1 –1 1 1
Andre Agassi 2 3 1 –1 1 1 1 1 1
David Nalbandian 8 10 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 13 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 1
Joachim Johansson 14 12 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 18 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 16 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 7 6 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 18 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Nicolas Massu 13 11 1 1 1 1 –1 1 1 1 1 –1 1 1 1 1 1 1 1
Vince Spadea 17 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1 1
176
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.8
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 152
z = 4.9315312
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the DD01
binary SL-model.
177
Player
General
SL-
Model
DD01
Bin SL-
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 4 0
Safin, Marat 5 7 4
Moya, Carlos 10 14 16
Henman, Tim 9 9 0
Coria, Guillermo 6 5 1
Agassi, Andre 2 3 1
Nalbandian, David 8 10 4
Gaudio, Gaston 12 13 1
Canas, Guillermo 11 8 9
Johansson, Joachim 14 12 4
Robredo, Tommy 18 20 4
Hrbaty, Dominik 20 16 16
Grosjean, Sebastien 15 17 4
Youzhny, Mikhail 7 6 1
Haas, Tommy 16 18 4
Massu, Nicolas 13 11 4
Spadea, Vincent 17 15 4
Kiefer, Nicolas 19 19 0
Total 78
ρ = 0.941353
178
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.941353
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.103264
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the DD01
binary SL-model.
7.7.4 General SL-Model vs Binomial Poisson Model (Bayesian Solution)
1 for agreement and
–1 for disagreement
General S
L-M
odel
Binomial P
oisso
n B
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 7 1 1
Marat Safin 5 5 1 1 –1
Carlos Moya 10 10 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 6 4 1 1 –1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 12 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 14 15 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 18 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 15 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 6 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 13 16 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1 –1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 –1
180
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.84210526
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 160
z = 5.19108548
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the bayesian
binomial poisson model.
181
Player
General
SL-
Model
Binomial
Poisson
B
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 7 9
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 9 8 1
Coria, Guillermo 6 4 4
Agassi, Andre 2 2 0
Nalbandian, David 8 9 1
Gaudio, Gaston 12 12 0
Canas, Guillermo 11 11 0
Johansson, Joachim 14 15 1
Robredo, Tommy 18 19 1
Hrbaty, Dominik 20 18 4
Grosjean, Sebastien 15 13 4
Youzhny, Mikhail 7 6 1
Haas, Tommy 16 14 4
Massu, Nicolas 13 16 9
Spadea, Vincent 17 20 9
Kiefer, Nicolas 19 17 4
Total 52
ρ = 0.960902
182
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.960902
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.188476
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the SL-model and the ranks obtained by the bayesian binomial
poisson model.
7.7.5 General SL-Model vs Binomial Poisson Model (Max. Like. Solution)
1 for agreement and
–1 for disagreement
General S
L-M
odel
Binomial P
oisso
n M
L
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 5 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 13 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 14 12 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 20 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 13 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
184
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.96842105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 184
z = 5.9697483
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the maximum
likelihood binomial poisson model.
185
Player
General
SL-
Model
Binomial
Poisson
ML
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 9 8 1
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 9 1
Gaudio, Gaston 12 13 1
Canas, Guillermo 11 11 0
Johansson, Joachim 14 12 4
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 20 0
Grosjean, Sebastien 15 15 0
Youzhny, Mikhail 7 7 0
Haas, Tommy 16 16 0
Massu, Nicolas 13 14 1
Spadea, Vincent 17 17 0
Kiefer, Nicolas 19 19 0
Total 8
ρ = 0.993985
186
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.993985
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.33268
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the maximum
likelihood binomial poisson model.
7.7.6 General SL-Model vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 5 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 8 1 1 1 1 1 1 1 1
Gaston Gaudio 12 12 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 14 13 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 20 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 13 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
188
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.98947368
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 188
z = 6.09952543
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the Bradley-
Terry model.
189
Player
General
SL-
Model
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 9 9 0
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 8 0
Gaudio, Gaston 12 12 0
Canas, Guillermo 11 11 0
Johansson, Joachim 14 13 1
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 20 0
Grosjean, Sebastien 15 15 0
Youzhny, Mikhail 7 7 0
Haas, Tommy 16 16 0
Massu, Nicolas 13 14 1
Spadea, Vincent 17 17 0
Kiefer, Nicolas 19 19 0
Total 2
ρ = 0.998496
190
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.998496
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.352344
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the SL-model and the ranks obtained by the Bradley-Terry
model.
7.7.7 General SL-Model vs Poisson Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 7 1 1 1
Carlos Moya 10 11 1 1 1 1
Tim Henman 9 12 1 1 1 1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 8 1 1 1 1 1 1 1 1
Gaston Gaudio 12 9 1 1 1 1 –1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 –1 –1 1 1 1 –1
Joachim Johansson 14 17 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 20 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 5 1 1 1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 13 13 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 –1
192
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.83157895
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 158
z = 5.12619691
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the poisson
model.
193
Player
General
SL-
Model
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 7 4
Moya, Carlos 10 11 1
Henman, Tim 9 12 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 8 0
Gaudio, Gaston 12 9 9
Canas, Guillermo 11 10 1
Johansson, Joachim 14 17 9
Robredo, Tommy 18 16 4
Hrbaty, Dominik 20 18 4
Grosjean, Sebastien 15 14 1
Youzhny, Mikhail 7 5 4
Haas, Tommy 16 15 1
Massu, Nicolas 13 13 0
Spadea, Vincent 17 20 9
Kiefer, Nicolas 19 19 0
Total 56
ρ = 0.957895
194
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.957895
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.175366
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the poisson
model.
7.7.8 General SL-Model vs Approx. Algorithm of Bayesian Solution Poisson Model
1 for agreement and
–1 for disagreement
General S
L-M
odel
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 5 14 1 1 1
Carlos Moya 10 11 1 1 1 –1
Tim Henman 9 12 1 1 1 –1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 –1 1 1 1 1
Gaston Gaudio 12 7 1 1 1 –1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 –1 –1 1 1 –1 –1
Joachim Johansson 14 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 4 1 1 –1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 13 10 1 1 1 –1 –1 –1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
196
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.69473684
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 132
z = 4.28264552
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
197
Player
General
SL-
Model
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 5 1
Safin, Marat 5 14 81
Moya, Carlos 10 11 1
Henman, Tim 9 12 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 9 1
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 14 16 4
Robredo, Tommy 18 17 1
Hrbaty, Dominik 20 15 25
Grosjean, Sebastien 15 13 4
Youzhny, Mikhail 7 4 9
Haas, Tommy 16 18 4
Massu, Nicolas 13 10 9
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 20 1
Total 188
ρ = 0.858647
198
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.858647
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.742754
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
7.7.9 General SL-Model vs Row Sum Method
1 for agreement and
–1 for disagreement
General S
L-M
odel
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
General SL-Model 1 3 4 5 10 9 6 2 8 12 11 14 18 20 15 7 16 13 17 19
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 5 4 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 8 12 1 1 1 1 –1 –1 1 1
Gaston Gaudio 12 7 1 1 1 1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 –1
Joachim Johansson 14 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 7 11 1 1 1 1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1
Nicolas Massu 13 17 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 –1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1
Nicolas Kiefer 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1 –1 –1 –1
200
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.63157895
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 120
z = 3.89331411
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the row sum
method.
201
Player
General
SL-
Model
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 3 1
Safin, Marat 5 4 1
Moya, Carlos 10 10 0
Henman, Tim 9 9 0
Coria, Guillermo 6 6 0
Agassi, Andre 2 5 9
Nalbandian, David 8 12 16
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 14 16 4
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 14 36
Grosjean, Sebastien 15 20 25
Youzhny, Mikhail 7 11 16
Haas, Tommy 16 15 1
Massu, Nicolas 13 17 16
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 13 36
Total 200
ρ = 0.849624
202
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.849624
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.703425
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the general SL-model and the ranks obtained by the row sum
method.
7.7.10 Binary SL-Model vs DDic01 Binary SL-Model
1 for agreement and
–1 for disagreement
Bin SL-M
odel
DDic0
1 Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 6 7 1 1 1
Carlos Moya 12 14 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 5 5 1 1 1 1 1 1
Andre Agassi 3 3 1 1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 10 10 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 13 12 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 20 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 15 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 19 16 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 7 6 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Massu 14 13 1 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Kiefer 18 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1
204
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.91578947
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 174
z = 5.64530546
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the DDic01
binary SL-model.
205
Player
Bin
SL-
Model
DDic01
Bin SL-
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 4 0
Safin, Marat 6 7 1
Moya, Carlos 12 14 4
Henman, Tim 8 8 0
Coria, Guillermo 5 5 0
Agassi, Andre 3 3 0
Nalbandian, David 9 9 0
Gaudio, Gaston 10 10 0
Canas, Guillermo 11 11 0
Johansson, Joachim 13 12 1
Robredo, Tommy 20 19 1
Hrbaty, Dominik 15 15 0
Grosjean, Sebastien 19 16 9
Youzhny, Mikhail 7 6 1
Haas, Tommy 17 20 9
Massu, Nicolas 14 13 1
Spadea, Vincent 16 17 1
Kiefer, Nicolas 18 18 0
Total 28
ρ = 0.978947
206
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.978947
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.267133
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the DDic01
binary SL-model.
7.7.11 Binary SL-Model vs DD01 Binary SL-Model
1 for agreement and
–1 for disagreement
Bin SL-M
odel
DD01 Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 6 7 1 1 1
Carlos Moya 12 14 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 5 1 1 1 1 1 1
Andre Agassi 3 3 1 1 1 1 1 1 1
David Nalbandian 9 10 1 1 1 1 1 1 1 1
Gaston Gaudio 10 13 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 8 1 1 1 1 1 –1 1 1 –1 –1
Joachim Johansson 13 12 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 16 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 19 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 7 6 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 17 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Nicolas Massu 14 11 1 1 1 1 –1 1 1 1 1 –1 1 –1 1 1 1 1 1
Vince Spadea 16 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
208
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.87368421
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 166
z = 5.38575118
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the DD01 binary
SL-model.
209
Player
Bin
SL-
Model
DD01
Bin SL-
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 4 0
Safin, Marat 6 7 1
Moya, Carlos 12 14 4
Henman, Tim 8 9 1
Coria, Guillermo 5 5 0
Agassi, Andre 3 3 0
Nalbandian, David 9 10 1
Gaudio, Gaston 10 13 9
Canas, Guillermo 11 8 9
Johansson, Joachim 13 12 1
Robredo, Tommy 20 20 0
Hrbaty, Dominik 15 16 1
Grosjean, Sebastien 19 17 4
Youzhny, Mikhail 7 6 1
Haas, Tommy 17 18 1
Massu, Nicolas 14 11 9
Spadea, Vincent 16 15 1
Kiefer, Nicolas 18 19 1
Total 44
ρ = 0.966917
210
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.966917
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.214695
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the DD01 binary
SL-model.
7.7.12 Binary SL-Model vs Binomial Poisson Model (Bayesian Solution)
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Binomial P
oisso
n B
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 7 1 1
Marat Safin 6 5 1 1 –1
Carlos Moya 12 10 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 5 4 1 1 –1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 10 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 13 15 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 20 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 7 6 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 17 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1
Nicolas Massu 14 16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Vince Spadea 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 –1 1
Nicolas Kiefer 18 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 –1
212
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.78947368
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 150
z = 4.86664263
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the bayesian
binomial poisson model.
213
Player
Bin
SL-
Model
Binomial
Poisson
B
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 7 9
Safin, Marat 6 5 1
Moya, Carlos 12 10 4
Henman, Tim 8 8 0
Coria, Guillermo 5 4 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 12 4
Canas, Guillermo 11 11 0
Johansson, Joachim 13 15 4
Robredo, Tommy 20 19 1
Hrbaty, Dominik 15 18 9
Grosjean, Sebastien 19 13 36
Youzhny, Mikhail 7 6 1
Haas, Tommy 17 14 9
Massu, Nicolas 14 16 4
Spadea, Vincent 16 20 16
Kiefer, Nicolas 18 17 1
Total 102
ρ = 0.923308
214
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.923308
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.024607
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the bayesian
binomial poisson model.
7.7.13 Binary SL-Model vs Binomial Poisson Model (Max. Like. Solution)
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Binomial P
oisso
n M
L
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 6 5 1 1 1
Carlos Moya 12 10 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 10 13 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 13 12 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 19 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 17 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
Nicolas Massu 14 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1 1
216
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.83157895
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 158
z = 5.12619691
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the maximum
likelihood binomial poisson model.
217
Player
Bin
SL-
Model
Binomial
Poisson
ML
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 6 5 1
Moya, Carlos 12 10 4
Henman, Tim 8 8 0
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 13 9
Canas, Guillermo 11 11 0
Johansson, Joachim 13 12 1
Robredo, Tommy 20 18 4
Hrbaty, Dominik 15 20 25
Grosjean, Sebastien 19 15 16
Youzhny, Mikhail 7 7 0
Haas, Tommy 17 16 1
Massu, Nicolas 14 14 0
Spadea, Vincent 16 17 1
Kiefer, Nicolas 18 19 1
Total 66
ρ = 0.950376
218
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.950376
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.142593
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the maximum
likelihood binomial poisson model.
7.7.14 Binary SL-Model vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 6 5 1 1 1
Carlos Moya 12 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 10 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 13 13 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 19 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 17 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
Nicolas Massu 14 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1 1
220
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.83157895
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 158
z = 5.12619691
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the Bradley-
Terry model.
221
Player
Bin
SL-
Model
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 6 5 1
Moya, Carlos 12 10 4
Henman, Tim 8 9 1
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 8 1
Gaudio, Gaston 10 12 4
Canas, Guillermo 11 11 0
Johansson, Joachim 13 13 0
Robredo, Tommy 20 18 4
Hrbaty, Dominik 15 20 25
Grosjean, Sebastien 19 15 16
Youzhny, Mikhail 7 7 0
Haas, Tommy 17 16 1
Massu, Nicolas 14 14 0
Spadea, Vincent 16 17 1
Kiefer, Nicolas 18 19 1
Total 62
ρ = 0.953383
222
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.953383
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.155702
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the Bradley-
Terry model.
7.7.15 Binary SL-Model vs Poisson Model
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 6 7 1 1 1
Carlos Moya 12 11 1 1 1 1
Tim Henman 8 12 1 1 1 1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 10 9 1 1 1 1 1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 1 –1 1 1 1 1
Joachim Johansson 13 17 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 20 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 15 18 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 19 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 7 5 1 1 1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 17 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1
Nicolas Massu 14 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 1 –1
224
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.77894737
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 148
z = 4.80175407
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the poisson
model.
225
Player
Bin
SL-
Model
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 6 7 1
Moya, Carlos 12 11 1
Henman, Tim 8 12 16
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 8 1
Gaudio, Gaston 10 9 1
Canas, Guillermo 11 10 1
Johansson, Joachim 13 17 16
Robredo, Tommy 20 16 16
Hrbaty, Dominik 15 18 9
Grosjean, Sebastien 19 14 25
Youzhny, Mikhail 7 5 4
Haas, Tommy 17 15 4
Massu, Nicolas 14 13 1
Spadea, Vincent 16 20 16
Kiefer, Nicolas 18 19 1
Total 116
ρ = 0.912782
226
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.912782
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.978724
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the poisson
model.
7.7.16 Binary SL-Model vs Approx. Algorithm of Bayesian Solution Poisson Model
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 6 14 1 1 1
Carlos Moya 12 11 1 1 1 –1
Tim Henman 8 12 1 1 1 –1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 –1 1 –1 1 1
Gaston Gaudio 10 7 1 1 1 –1 1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 1 –1 1 1 –1 1
Joachim Johansson 13 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 20 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 15 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 19 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 7 4 1 1 –1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 17 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Massu 14 10 1 1 1 –1 –1 –1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 16 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 –1 1
Nicolas Kiefer 18 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 1 1
228
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.68421053
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 130
z = 4.21775695
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the approximate
algorithm of the bayesian solution to the poisson model.
229
Player
Bin
SL-
Model
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 5 1
Safin, Marat 6 14 64
Moya, Carlos 12 11 1
Henman, Tim 8 12 16
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 7 9
Canas, Guillermo 11 8 9
Johansson, Joachim 13 16 9
Robredo, Tommy 20 17 9
Hrbaty, Dominik 15 15 0
Grosjean, Sebastien 19 13 36
Youzhny, Mikhail 7 4 9
Haas, Tommy 17 18 1
Massu, Nicolas 14 10 16
Spadea, Vincent 16 19 9
Kiefer, Nicolas 18 20 4
Total 196
ρ = 0.852632
230
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.852632
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.716535
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the approximate
algorithm of the bayesian solution to the poisson model.
7.7.17 Binary SL-Model vs Row Sum Method
1 for agreement and
–1 for disagreement
Bin SL-M
odel
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bin SL-Model 1 2 4 6 12 8 5 3 9 10 11 13 20 15 19 7 17 14 16 18
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 6 4 1 1 1
Carlos Moya 12 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 5 1 1 –1 –1 1 1 1
David Nalbandian 9 12 1 1 1 1 –1 1 1 1
Gaston Gaudio 10 7 1 1 1 1 1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 1 –1 1 1 –1 1
Joachim Johansson 13 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 14 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 19 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 7 11 1 1 1 1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 17 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 14 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1
Vince Spadea 16 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1
Nicolas Kiefer 18 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 –1 –1 –1
232
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.74736842
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 142
z = 4.60708836
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the row sum
method.
233
Player
Bin
SL-
Model
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 3 1
Safin, Marat 6 4 4
Moya, Carlos 12 10 4
Henman, Tim 8 9 1
Coria, Guillermo 5 6 1
Agassi, Andre 3 5 4
Nalbandian, David 9 12 9
Gaudio, Gaston 10 7 9
Canas, Guillermo 11 8 9
Johansson, Joachim 13 16 9
Robredo, Tommy 20 18 4
Hrbaty, Dominik 15 14 1
Grosjean, Sebastien 19 20 1
Youzhny, Mikhail 7 11 16
Haas, Tommy 17 15 4
Massu, Nicolas 14 17 9
Spadea, Vincent 16 19 9
Kiefer, Nicolas 18 13 25
Total 120
ρ = 0.909774
234
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.909774
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.965615
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the binary SL-model and the ranks obtained by the row sum
method.
7.7.18 DDic01 Binary SL-Model vs DD01 Binary SL-Model
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
DD01 Bin SL-M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 7 1 1 1
Carlos Moya 14 14 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 5 1 1 1 1 1 1
Andre Agassi 3 3 1 1 1 1 1 1 1
David Nalbandian 9 10 1 1 1 1 1 1 1 1
Gaston Gaudio 10 13 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 8 1 1 1 1 1 –1 1 1 –1 –1
Joachim Johansson 12 12 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 19 20 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 16 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 6 6 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 20 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Massu 13 11 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 1 1 1
Vince Spadea 17 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
236
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.89473684
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 170
z = 5.51552832
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
DD01 binary SL-model.
237
Player
DDic01
Bin SL-
Model
DD01
Bin SL-
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 4 0
Safin, Marat 7 7 0
Moya, Carlos 14 14 0
Henman, Tim 8 9 1
Coria, Guillermo 5 5 0
Agassi, Andre 3 3 0
Nalbandian, David 9 10 1
Gaudio, Gaston 10 13 9
Canas, Guillermo 11 8 9
Johansson, Joachim 12 12 0
Robredo, Tommy 19 20 1
Hrbaty, Dominik 15 16 1
Grosjean, Sebastien 16 17 1
Youzhny, Mikhail 6 6 0
Haas, Tommy 20 18 4
Massu, Nicolas 13 11 4
Spadea, Vincent 17 15 4
Kiefer, Nicolas 18 19 1
Total 36
ρ = 0.972932
238
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.972932
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.240914
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
DD01 binary SL-model.
7.7.19 DDic01 Binary SL-Model vs Binomial Poisson Model (Bayesian Solution)
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Binomial P
oisso
n B
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 7 1 1
Marat Safin 7 5 1 1 –1
Carlos Moya 14 10 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 5 4 1 1 –1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 10 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 12 15 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 19 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 16 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 6 1 1 –1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 20 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1
Nicolas Massu 13 16 1 1 1 1 –1 1 1 1 1 1 1 1 1 1 –1 1 –1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1
Nicolas Kiefer 18 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1 –1
240
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.76842105
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 146
z = 4.7368655
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
bayesian binomial poisson model.
241
Player
DDic01
Bin SL-
Model
Binomial
Poisson B
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 7 9
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 8 8 0
Coria, Guillermo 5 4 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 12 4
Canas, Guillermo 11 11 0
Johansson, Joachim 12 15 9
Robredo, Tommy 19 19 0
Hrbaty, Dominik 15 18 9
Grosjean, Sebastien 16 13 9
Youzhny, Mikhail 6 6 0
Haas, Tommy 20 14 36
Massu, Nicolas 13 16 9
Spadea, Vincent 17 20 9
Kiefer, Nicolas 18 17 1
Total 118
ρ = 0.911278
242
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.911278
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.97217
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
bayesian binomial poisson model.
7.7.20 DDic01 Binary SL-Model vs Binomial Poisson Model (Max. Like. Solution)
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Binomial P
oisso
n M
L
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 5 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 10 13 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 12 12 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 16 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 6 7 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 20 16 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 13 14 1 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 –1 1 1
244
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.81052632
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 154
z = 4.99641977
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
maximum likelihood binomial poisson model.
245
Player
DDic01
Bin SL-
Model
Binomial
Poisson ML
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 8 8 0
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 13 9
Canas, Guillermo 11 11 0
Johansson, Joachim 12 12 0
Robredo, Tommy 19 18 1
Hrbaty, Dominik 15 20 25
Grosjean, Sebastien 16 15 1
Youzhny, Mikhail 6 7 1
Haas, Tommy 20 16 16
Massu, Nicolas 13 14 1
Spadea, Vincent 17 17 0
Kiefer, Nicolas 18 19 1
Total 78
ρ = 0.941353
246
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.941353
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.103264
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
maximum likelihood binomial poisson model.
7.7.21 DDic01 Binary SL-Model vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 5 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 10 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 –1 1 1 1 1 –1
Joachim Johansson 12 13 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 16 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 6 7 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 20 16 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 13 14 1 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 –1 1 1
248
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.81052632
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 154
z = 4.99641977
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
Bradley-Terry model.
249
Player
DDic01
Bin SL-
Model
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 8 9 1
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 8 1
Gaudio, Gaston 10 12 4
Canas, Guillermo 11 11 0
Johansson, Joachim 12 13 1
Robredo, Tommy 19 18 1
Hrbaty, Dominik 15 20 25
Grosjean, Sebastien 16 15 1
Youzhny, Mikhail 6 7 1
Haas, Tommy 20 16 16
Massu, Nicolas 13 14 1
Spadea, Vincent 17 17 0
Kiefer, Nicolas 18 19 1
Total 76
ρ = 0.942857
250
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.942857
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.109819
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
Bradley-Terry model.
7.7.22 DDic01 Binary SL-Model vs Poisson Model
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 7 1 1 1
Carlos Moya 14 11 1 1 1 1
Tim Henman 8 12 1 1 1 1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 10 9 1 1 1 1 1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 1 –1 1 1 1 1
Joachim Johansson 12 17 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 19 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 15 18 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 16 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 5 1 1 1 1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 20 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1
Nicolas Massu 13 13 1 1 1 1 –1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1 –1
252
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.77894737
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 148
z = 4.80175407
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
poisson model.
253
Player
DDic01
Bin SL-
Model
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 7 0
Moya, Carlos 14 11 9
Henman, Tim 8 12 16
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 8 1
Gaudio, Gaston 10 9 1
Canas, Guillermo 11 10 1
Johansson, Joachim 12 17 25
Robredo, Tommy 19 16 9
Hrbaty, Dominik 15 18 9
Grosjean, Sebastien 16 14 4
Youzhny, Mikhail 6 5 1
Haas, Tommy 20 15 25
Massu, Nicolas 13 13 0
Spadea, Vincent 17 20 9
Kiefer, Nicolas 18 19 1
Total 114
ρ = 0.914286
254
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.914286
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.985279
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
poisson model.
7.7.23 DDic01 Binary SL-Model vs Approx. Algorithm of Bayesian Solution Poisson
Model
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 7 14 1 1 1
Carlos Moya 14 11 1 1 1 –1
Tim Henman 8 12 1 1 1 –1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 –1 1 –1 1 1
Gaston Gaudio 10 7 1 1 1 –1 1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 1 –1 1 1 –1 1
Joachim Johansson 12 16 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 19 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 15 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 16 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 4 1 1 –1 1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 20 18 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 13 10 1 1 1 –1 1 –1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1
Nicolas Kiefer 18 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 –1 1 –1
256
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.72631579
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 138
z = 4.47731122
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
257
Player
DDic01
Bin SL-
Model
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 5 1
Safin, Marat 7 14 49
Moya, Carlos 14 11 9
Henman, Tim 8 12 16
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 9 9 0
Gaudio, Gaston 10 7 9
Canas, Guillermo 11 8 9
Johansson, Joachim 12 16 16
Robredo, Tommy 19 17 4
Hrbaty, Dominik 15 15 0
Grosjean, Sebastien 16 13 9
Youzhny, Mikhail 6 4 4
Haas, Tommy 20 18 4
Massu, Nicolas 13 10 9
Spadea, Vincent 17 19 4
Kiefer, Nicolas 18 20 4
Total 150
ρ = 0.887218
258
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.887218
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.867294
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
7.7.24 DDic01 Binary SL-Model vs Row Sum Method
1 for agreement and
–1 for disagreement
DDic0
1 Bin SL-M
odel
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DDic01 Bin SL-Model 1 2 4 7 14 8 5 3 9 10 11 12 19 15 16 6 20 13 17 18
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 7 4 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 5 1 1 –1 –1 1 1 1
David Nalbandian 9 12 1 1 1 1 –1 1 1 1
Gaston Gaudio 10 7 1 1 1 1 1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 1 –1 1 1 –1 1
Joachim Johansson 12 16 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 14 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 6 11 1 1 1 –1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 20 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1
Nicolas Massu 13 17 1 1 1 1 –1 1 1 1 1 1 1 1 1 –1 1 1 –1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 –1 1
Nicolas Kiefer 18 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1 1 –1 –1
260
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.68421053
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 130
z = 4.21775695
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the row
sum method.
261
Player
DDic01
Bin SL-
Model
Row Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 3 1
Safin, Marat 7 4 9
Moya, Carlos 14 10 16
Henman, Tim 8 9 1
Coria, Guillermo 5 6 1
Agassi, Andre 3 5 4
Nalbandian, David 9 12 9
Gaudio, Gaston 10 7 9
Canas, Guillermo 11 8 9
Johansson, Joachim 12 16 16
Robredo, Tommy 19 18 1
Hrbaty, Dominik 15 14 1
Grosjean, Sebastien 16 20 16
Youzhny, Mikhail 6 11 25
Haas, Tommy 20 15 25
Massu, Nicolas 13 17 16
Spadea, Vincent 17 19 4
Kiefer, Nicolas 18 13 25
Total 188
ρ = 0.858647
262
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.858647
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.742754
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DDic01 binary SL-model and the ranks obtained by the row
sum method.
7.7.25 DD01 Binary SL-Model vs Binomial Poisson Model (Bayesian Solution)
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Binomial P
oisso
n B
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 7 1 1
Marat Safin 7 5 1 1 –1
Carlos Moya 14 10 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 5 4 1 1 –1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 10 9 1 1 1 1 1 1 1 1
Gaston Gaudio 13 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 8 11 1 1 1 1 –1 –1 1 1 –1 1
Joachim Johansson 12 15 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 19 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 16 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 17 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 6 1 1 –1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 18 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1
Nicolas Massu 11 16 1 1 1 1 –1 1 1 1 1 –1 1 –1 1 1 –1 1 –1
Vince Spadea 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 1
Nicolas Kiefer 19 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 –1
264
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.72631579
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 138
z = 4.47731122
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
bayesian binomial poisson model.
265
Player
DD01
Bin SL-
Model
Binomial
Poisson B
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 7 9
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 9 8 1
Coria, Guillermo 5 4 1
Agassi, Andre 3 2 1
Nalbandian, David 10 9 1
Gaudio, Gaston 13 12 1
Canas, Guillermo 8 11 9
Johansson, Joachim 12 15 9
Robredo, Tommy 20 19 1
Hrbaty, Dominik 16 18 4
Grosjean, Sebastien 17 13 16
Youzhny, Mikhail 6 6 0
Haas, Tommy 18 14 16
Massu, Nicolas 11 16 25
Spadea, Vincent 15 20 25
Kiefer, Nicolas 19 17 4
Total 144
ρ = 0.891729
266
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.891729
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.886958
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
bayesian binomial poisson model.
7.7.26 DD01 Binary SL-Model vs Binomial Poisson Model (Max. Like. Solution)
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Binomial P
oisso
n M
L
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 5 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 9 8 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 10 9 1 1 1 1 1 1 1 1
Gaston Gaudio 13 13 1 1 1 1 –1 1 1 1 1
Guillermo Canas 8 11 1 1 1 1 –1 –1 1 1 –1 1
Joachim Johansson 12 12 1 1 1 1 –1 1 1 1 1 1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 17 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 6 7 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 18 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Nicolas Massu 11 14 1 1 1 1 –1 1 1 1 1 –1 1 –1 1 1 1 1 1
Vince Spadea 15 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1 1
268
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.81052632
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 154
z = 4.99641977
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
maximum likelihood binomial poisson model.
269
Player
DD01
Bin SL-
Model
Binomial
Poisson
ML
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 9 8 1
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 10 9 1
Gaudio, Gaston 13 13 0
Canas, Guillermo 8 11 9
Johansson, Joachim 12 12 0
Robredo, Tommy 20 18 4
Hrbaty, Dominik 16 20 16
Grosjean, Sebastien 17 15 4
Youzhny, Mikhail 6 7 1
Haas, Tommy 18 16 4
Massu, Nicolas 11 14 9
Spadea, Vincent 15 17 4
Kiefer, Nicolas 19 19 0
Total 76
ρ = 0.942857
270
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.942857
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.109819
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
maximum likelihood binomial poisson model.
7.7.27 DD01 Binary SL-Model vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 5 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 10 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 13 12 1 1 1 1 –1 1 1 1 1
Guillermo Canas 8 11 1 1 1 1 –1 –1 1 1 –1 1
Joachim Johansson 12 13 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 16 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 17 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
Mikhail Youzhny 6 7 1 1 1 –1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 18 16 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Nicolas Massu 11 14 1 1 1 1 –1 1 1 1 1 –1 1 –1 1 1 1 1 1
Vince Spadea 15 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1 1
272
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.78947368
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 150
z = 4.86664263
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
Bradley-Terry model.
273
Player
DD01
Bin SL-
Model
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 5 4
Moya, Carlos 14 10 16
Henman, Tim 9 9 0
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 10 8 4
Gaudio, Gaston 13 12 1
Canas, Guillermo 8 11 9
Johansson, Joachim 12 13 1
Robredo, Tommy 20 18 4
Hrbaty, Dominik 16 20 16
Grosjean, Sebastien 17 15 4
Youzhny, Mikhail 6 7 1
Haas, Tommy 18 16 4
Massu, Nicolas 11 14 9
Spadea, Vincent 15 17 4
Kiefer, Nicolas 19 19 0
Total 80
ρ = 0.93985
274
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.93985
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.09671
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
Bradley-Terry model.
7.7.28 DD01 Binary SL-Model vs Poisson Model
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 7 7 1 1 1
Carlos Moya 14 11 1 1 1 1
Tim Henman 9 12 1 1 1 1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 10 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 13 9 1 1 1 1 1 –1 1 1 1
Guillermo Canas 8 10 1 1 1 1 1 1 1 1 –1 –1
Joachim Johansson 12 17 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 16 18 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 17 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 5 1 1 1 1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 18 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1
Nicolas Massu 11 13 1 1 1 1 –1 1 1 1 1 –1 1 1 1 1 1 1 1
Vince Spadea 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 –1
276
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.75789474
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 144
z = 4.67197693
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
poisson model.
277
Player
DD01
Bin SL-
Model
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 4 0
Safin, Marat 7 7 0
Moya, Carlos 14 11 9
Henman, Tim 9 12 9
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 10 8 4
Gaudio, Gaston 13 9 16
Canas, Guillermo 8 10 4
Johansson, Joachim 12 17 25
Robredo, Tommy 20 16 16
Hrbaty, Dominik 16 18 4
Grosjean, Sebastien 17 14 9
Youzhny, Mikhail 6 5 1
Haas, Tommy 18 15 9
Massu, Nicolas 11 13 4
Spadea, Vincent 15 20 25
Kiefer, Nicolas 19 19 0
Total 138
ρ = 0.896241
278
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.896241
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.906622
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
poisson model.
7.7.29 DD01 Binary SL-Model vs Approx. Algorithm of Bayesian Solution Poisson Model
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 2 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 7 14 1 1 1
Carlos Moya 14 11 1 1 1 –1
Tim Henman 9 12 1 1 1 –1 –1
Guillermo Coria 5 6 1 1 1 1 1 1
Andre Agassi 3 2 1 –1 1 1 1 1 1
David Nalbandian 10 9 1 1 1 –1 1 –1 1 1
Gaston Gaudio 13 7 1 1 1 –1 1 –1 1 1 –1
Guillermo Canas 8 8 1 1 1 –1 1 1 1 1 1 –1
Joachim Johansson 12 16 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 17 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 –1
Mikhail Youzhny 6 4 1 1 –1 1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 18 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Massu 11 10 1 1 1 –1 1 –1 1 1 1 –1 1 1 1 1 1 1 1
Vince Spadea 15 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 –1 1
Nicolas Kiefer 19 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 1
280
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.70526316
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 134
z = 4.34753409
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
281
Player
DD01
Bin SL-
Model
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 3 1
Hewitt, Lleyton 4 5 1
Safin, Marat 7 14 49
Moya, Carlos 14 11 9
Henman, Tim 9 12 9
Coria, Guillermo 5 6 1
Agassi, Andre 3 2 1
Nalbandian, David 10 9 1
Gaudio, Gaston 13 7 36
Canas, Guillermo 8 8 0
Johansson, Joachim 12 16 16
Robredo, Tommy 20 17 9
Hrbaty, Dominik 16 15 1
Grosjean, Sebastien 17 13 16
Youzhny, Mikhail 6 4 4
Haas, Tommy 18 18 0
Massu, Nicolas 11 10 1
Spadea, Vincent 15 19 16
Kiefer, Nicolas 19 20 1
Total 172
ρ = 0.870677
282
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.870677
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.795192
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
7.7.30 DD01 Binary SL-Model vs Row Sum Method
1 for agreement and
–1 for disagreement
DD01 Bin SL-M
odel
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
DD01 Bin SL-Model 1 2 4 7 14 9 5 3 10 13 8 12 20 16 17 6 18 11 15 19
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 2 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 7 4 1 1 1
Carlos Moya 14 10 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 5 6 1 1 1 –1 1 1
Andre Agassi 3 5 1 1 –1 –1 1 1 1
David Nalbandian 10 12 1 1 1 1 –1 1 1 1
Gaston Gaudio 13 7 1 1 1 1 1 –1 1 1 –1
Guillermo Canas 8 8 1 1 1 1 1 1 1 1 1 –1
Joachim Johansson 12 16 1 1 1 1 –1 1 1 1 1 –1 1
Tommy Robredo 20 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 16 14 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 1
Mikhail Youzhny 6 11 1 1 1 –1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 18 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1
Nicolas Massu 11 17 1 1 1 1 –1 1 1 1 1 –1 1 –1 1 –1 1 1 –1
Vince Spadea 15 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 –1 1
Nicolas Kiefer 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1 –1 –1 –1
284
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.66315789
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 126
z = 4.08797981
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the row
sum method.
285
Player
DD01
Bin SL-
Model
Row Sum
Method
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 2 2 0
Hewitt, Lleyton 4 3 1
Safin, Marat 7 4 9
Moya, Carlos 14 10 16
Henman, Tim 9 9 0
Coria, Guillermo 5 6 1
Agassi, Andre 3 5 4
Nalbandian, David 10 12 4
Gaudio, Gaston 13 7 36
Canas, Guillermo 8 8 0
Johansson, Joachim 12 16 16
Robredo, Tommy 20 18 4
Hrbaty, Dominik 16 14 4
Grosjean, Sebastien 17 20 9
Youzhny, Mikhail 6 11 25
Haas, Tommy 18 15 9
Massu, Nicolas 11 17 36
Spadea, Vincent 15 19 16
Kiefer, Nicolas 19 13 36
Total 226
ρ = 0.830075
286
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.830075
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.618214
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the DD01 binary SL-model and the ranks obtained by the row
sum method.
7.7.31 Binomial Poisson Model (Bayesian Solution) vs Binomial Poisson Model (Max.
Like. Solution)
1 for agreement and
–1 for disagreement
Binomial P
oisso
n B
Binomial P
oisso
n M
L
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 7 4 1 1
Marat Safin 5 5 1 1 –1
Carlos Moya 10 10 1 1 1 1
Tim Henman 8 8 1 1 1 1 1
Guillermo Coria 4 6 1 1 –1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 1 1 1 1 1
Gaston Gaudio 12 13 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 15 12 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 18 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 13 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 6 7 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 14 16 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 16 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Vince Spadea 20 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 –1
288
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.85263158
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 162
z = 5.25597404
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the maximum likelihood binomial poisson model.
289
Player
Binomial
Poisson
B
Binomial
Poisson
ML
Squared
difference of
the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 7 4 9
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 8 8 0
Coria, Guillermo 4 6 4
Agassi, Andre 2 2 0
Nalbandian, David 9 9 0
Gaudio, Gaston 12 13 1
Canas, Guillermo 11 11 0
Johansson, Joachim 15 12 9
Robredo, Tommy 19 18 1
Hrbaty, Dominik 18 20 4
Grosjean, Sebastien 13 15 4
Youzhny, Mikhail 6 7 1
Haas, Tommy 14 16 4
Massu, Nicolas 16 14 4
Spadea, Vincent 20 17 9
Kiefer, Nicolas 17 19 4
Total 54
ρ = 0.959398
290
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.959398
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.181921
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the maximum likelihood binomial poisson model.
7.7.32 Binomial Poisson Model (Bayesian Solution) vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n B
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 7 4 1 1
Marat Safin 5 5 1 1 –1
Carlos Moya 10 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 4 6 1 1 –1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 12 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 15 13 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 18 20 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 13 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 6 7 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 14 16 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 16 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1
Vince Spadea 20 17 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1 –1
292
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.85263158
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 162
z = 5.25597404
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the Bradley-Terry model.
293
Player
Binomial
Poisson
B
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 7 4 9
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 8 9 1
Coria, Guillermo 4 6 4
Agassi, Andre 2 2 0
Nalbandian, David 9 8 1
Gaudio, Gaston 12 12 0
Canas, Guillermo 11 11 0
Johansson, Joachim 15 13 4
Robredo, Tommy 19 18 1
Hrbaty, Dominik 18 20 4
Grosjean, Sebastien 13 15 4
Youzhny, Mikhail 6 7 1
Haas, Tommy 14 16 4
Massu, Nicolas 16 14 4
Spadea, Vincent 20 17 9
Kiefer, Nicolas 17 19 4
Total 50
ρ = 0.962406
294
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.962406
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.195031
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the Bradley-Terry model.
7.7.33 Binomial Poisson Model (Bayesian Solution) vs Poisson Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n B
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 7 4 1 1
Marat Safin 5 7 1 1 –1
Carlos Moya 10 11 1 1 1 1
Tim Henman 8 12 1 1 1 1 –1
Guillermo Coria 4 6 1 1 –1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 12 9 1 1 1 1 –1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 –1 –1 1 1 1 –1
Joachim Johansson 15 17 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 19 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 18 18 1 1 1 1 1 1 1 1 1 1 1 1 –1
Sebastien Grosjean 13 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 6 5 1 1 –1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 14 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 16 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1 –1
Vince Spadea 20 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1 1
296
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.8
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 152
z = 4.9315312
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the poisson model.
297
Player
Binomial
Poisson
B
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 7 4 9
Safin, Marat 5 7 4
Moya, Carlos 10 11 1
Henman, Tim 8 12 16
Coria, Guillermo 4 6 4
Agassi, Andre 2 2 0
Nalbandian, David 9 8 1
Gaudio, Gaston 12 9 9
Canas, Guillermo 11 10 1
Johansson, Joachim 15 17 4
Robredo, Tommy 19 16 9
Hrbaty, Dominik 18 18 0
Grosjean, Sebastien 13 14 1
Youzhny, Mikhail 6 5 1
Haas, Tommy 14 15 1
Massu, Nicolas 16 13 9
Spadea, Vincent 20 20 0
Kiefer, Nicolas 17 19 4
Total 74
ρ = 0.944361
298
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.944361
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.116374
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the poisson model.
7.7.34 Binomial Poisson Model (Bayesian Solution) vs Approx. Algorithm of Bayesian
Solution Poisson Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n B
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 7 5 1 1
Marat Safin 5 14 1 1 –1
Carlos Moya 10 11 1 1 1 –1
Tim Henman 8 12 1 1 1 –1 –1
Guillermo Coria 4 6 1 1 –1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 –1 1 –1 1 1
Gaston Gaudio 12 7 1 1 1 –1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 –1 –1 1 1 –1 –1
Joachim Johansson 15 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 19 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 18 15 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 13 13 1 1 1 –1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 6 4 1 1 1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 14 18 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1
Nicolas Massu 16 10 1 1 1 –1 –1 –1 1 1 1 1 1 –1 1 1 –1 1 –1
Vince Spadea 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1 –1
300
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.66315789
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 126
z = 4.08797981
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the approximate algorithm of the bayesian solution to the poisson model.
301
Player
Binomial
Poisson
B
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 7 5 4
Safin, Marat 5 14 81
Moya, Carlos 10 11 1
Henman, Tim 8 12 16
Coria, Guillermo 4 6 4
Agassi, Andre 2 2 0
Nalbandian, David 9 9 0
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 15 16 1
Robredo, Tommy 19 17 4
Hrbaty, Dominik 18 15 9
Grosjean, Sebastien 13 13 0
Youzhny, Mikhail 6 4 4
Haas, Tommy 14 18 16
Massu, Nicolas 16 10 36
Spadea, Vincent 20 19 1
Kiefer, Nicolas 17 20 9
Total 220
ρ = 0.834586
302
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.834586
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.637878
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the approximate algorithm of bayesian solution to the poisson model.
7.7.35 Binomial Poisson Model (Bayesian Solution) vs Row Sum Method
1 for agreement and
–1 for disagreement
Binomial P
oisso
n B
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson B 1 3 7 5 10 8 4 2 9 12 11 15 19 18 13 6 14 16 20 17
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 7 3 1 1
Marat Safin 5 4 1 1 –1
Carlos Moya 10 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 4 6 1 1 –1 –1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 9 12 1 1 1 1 –1 1 1 1
Gaston Gaudio 12 7 1 1 1 1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 –1
Joachim Johansson 15 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 19 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 18 14 1 1 1 1 1 1 1 1 1 1 1 –1 1
Sebastien Grosjean 13 20 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1
Mikhail Youzhny 6 11 1 1 –1 1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 14 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
Nicolas Massu 16 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Vince Spadea 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Kiefer 17 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1 1 –1 –1 1
304
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.66315789
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 126
z = 4.08797981
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the row sum method.
305
Player
Binomial
Poisson
B
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 7 3 16
Safin, Marat 5 4 1
Moya, Carlos 10 10 0
Henman, Tim 8 9 1
Coria, Guillermo 4 6 4
Agassi, Andre 2 5 9
Nalbandian, David 9 12 9
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 15 16 1
Robredo, Tommy 19 18 1
Hrbaty, Dominik 18 14 16
Grosjean, Sebastien 13 20 49
Youzhny, Mikhail 6 11 25
Haas, Tommy 14 15 1
Massu, Nicolas 16 17 1
Spadea, Vincent 20 19 1
Kiefer, Nicolas 17 13 16
Total 186
ρ = 0.86015
306
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.86015
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.749309
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the bayesian binomial poisson model and the ranks obtained by
the row sum method.
7.7.36 Binomial Poisson Model (Max. Like. Solution) vs Bradley-Terry Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n M
L
Brad
ley-Terry
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 5 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 13 12 1 1 1 1 1 1 1 1 1
Guillermo Canas 11 11 1 1 1 1 1 1 1 1 1 1
Joachim Johansson 12 13 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 20 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 7 7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 16 16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Massu 14 14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 17 17 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
308
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.97894737
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 186
z = 6.03463687
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the Bradley-Terry model.
309
Player
Binomial
Poisson
ML
Bradley-
Terry
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 5 0
Moya, Carlos 10 10 0
Henman, Tim 8 9 1
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 9 8 1
Gaudio, Gaston 13 12 1
Canas, Guillermo 11 11 0
Johansson, Joachim 12 13 1
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 20 0
Grosjean, Sebastien 15 15 0
Youzhny, Mikhail 7 7 0
Haas, Tommy 16 16 0
Massu, Nicolas 14 14 0
Spadea, Vincent 17 17 0
Kiefer, Nicolas 19 19 0
Total 4
ρ = 0.996992
310
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.996992
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.345789
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the Bradley-Terry model.
7.7.37 Binomial Poisson Model (Max. Like. Solution) vs Poisson Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n M
L
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 7 1 1 1
Carlos Moya 10 11 1 1 1 1
Tim Henman 8 12 1 1 1 1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 8 1 1 1 1 1 –1 1 1
Gaston Gaudio 13 9 1 1 1 1 –1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 –1 –1 1 1 1 –1
Joachim Johansson 12 17 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 18 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 20 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 5 1 1 1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 14 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 –1
312
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.8
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 152
z = 4.9315312
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the poisson model.
313
Player
Binomial
Poisson
ML
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 7 4
Moya, Carlos 10 11 1
Henman, Tim 8 12 16
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 9 8 1
Gaudio, Gaston 13 9 16
Canas, Guillermo 11 10 1
Johansson, Joachim 12 17 25
Robredo, Tommy 18 16 4
Hrbaty, Dominik 20 18 4
Grosjean, Sebastien 15 14 1
Youzhny, Mikhail 7 5 4
Haas, Tommy 16 15 1
Massu, Nicolas 14 13 1
Spadea, Vincent 17 20 9
Kiefer, Nicolas 19 19 0
Total 88
ρ = 0.933835
314
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.933835
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.070491
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the poisson model.
7.7.38 Binomial Poisson Model (Max. Like. Solution) vs Approx. Algorithm of Bayesian
Solution Poisson Model
1 for agreement and
–1 for disagreement
Binomial P
oisso
n M
L
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 5 14 1 1 1
Carlos Moya 10 11 1 1 1 –1
Tim Henman 8 12 1 1 1 –1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 9 9 1 1 1 –1 1 –1 1 1
Gaston Gaudio 13 7 1 1 1 –1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 –1 –1 1 1 –1 –1
Joachim Johansson 12 16 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 18 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 4 1 1 –1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 14 10 1 1 1 –1 –1 –1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
316
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.66315789
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 126
z = 4.08797981
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the approximate algorithm of the bayesian solution to the poisson model.
317
Player
Binomial
Poisson
ML
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 5 1
Safin, Marat 5 14 81
Moya, Carlos 10 11 1
Henman, Tim 8 12 16
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 9 9 0
Gaudio, Gaston 13 7 36
Canas, Guillermo 11 8 9
Johansson, Joachim 12 16 16
Robredo, Tommy 18 17 1
Hrbaty, Dominik 20 15 25
Grosjean, Sebastien 15 13 4
Youzhny, Mikhail 7 4 9
Haas, Tommy 16 18 4
Massu, Nicolas 14 10 16
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 20 1
Total 224
ρ = 0.831579
318
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.831579
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.624769
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the approximate algorithm of the bayesian solution to the poisson model.
7.7.39 Binomial Poisson Model (Max. Like. Solution) vs Row Sum Method
1 for agreement and
–1 for disagreement
Binomial P
oisso
n M
L
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Binomial Poisson ML 1 3 4 5 10 8 6 2 9 13 11 12 18 20 15 7 16 14 17 19
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 5 4 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 8 9 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 9 12 1 1 1 1 –1 1 1 1
Gaston Gaudio 13 7 1 1 1 1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 –1
Joachim Johansson 12 16 1 1 1 1 1 1 1 1 1 –1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 7 11 1 1 1 1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1
Nicolas Massu 14 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1
Nicolas Kiefer 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1 –1 –1 –1
320
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.64210526
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 122
z = 3.95820268
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the row sum method.
321
Player
Binomial
Poisson
ML
Row Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 3 1
Safin, Marat 5 4 1
Moya, Carlos 10 10 0
Henman, Tim 8 9 1
Coria, Guillermo 6 6 0
Agassi, Andre 2 5 9
Nalbandian, David 9 12 9
Gaudio, Gaston 13 7 36
Canas, Guillermo 11 8 9
Johansson, Joachim 12 16 16
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 14 36
Grosjean, Sebastien 15 20 25
Youzhny, Mikhail 7 11 16
Haas, Tommy 16 15 1
Massu, Nicolas 14 17 9
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 13 36
Total 210
ρ = 0.842105
322
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.842105
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.670652
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the maximum likelihood binomial poisson model and the ranks
obtained by the row sum method.
7.7.40 Bradley-Terry Model vs Poisson Model
1 for agreement and
–1 for disagreement
Brad
ley-Terry
Poisso
n M
odel
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 4 1 1
Marat Safin 5 7 1 1 1
Carlos Moya 10 11 1 1 1 1
Tim Henman 9 12 1 1 1 1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 8 1 1 1 1 1 1 1 1
Gaston Gaudio 12 9 1 1 1 1 –1 –1 1 1 1
Guillermo Canas 11 10 1 1 1 1 –1 –1 1 1 1 –1
Joachim Johansson 13 17 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 16 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 20 18 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 15 14 1 1 1 1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 5 1 1 1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1
Nicolas Massu 14 13 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 –1
324
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.82105263
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 156
z = 5.06130834
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the poisson
model.
325
Player
Bradley-
Terry
Poisson
Model
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 4 0
Safin, Marat 5 7 4
Moya, Carlos 10 11 1
Henman, Tim 9 12 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 8 0
Gaudio, Gaston 12 9 9
Canas, Guillermo 11 10 1
Johansson, Joachim 13 17 16
Robredo, Tommy 18 16 4
Hrbaty, Dominik 20 18 4
Grosjean, Sebastien 15 14 1
Youzhny, Mikhail 7 5 4
Haas, Tommy 16 15 1
Massu, Nicolas 14 13 1
Spadea, Vincent 17 20 9
Kiefer, Nicolas 19 19 0
Total 64
ρ = 0.95188
326
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.95188
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.149147
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the poisson
model.
7.7.41 Bradley-Terry Model vs Approx. Algorithm of Bayesian Solution Poisson Model
1 for agreement and
–1 for disagreement
Brad
ley-Terry
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 5 14 1 1 1
Carlos Moya 10 11 1 1 1 –1
Tim Henman 9 12 1 1 1 –1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 –1 1 1 1 1
Gaston Gaudio 12 7 1 1 1 –1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 –1 –1 –1 1 1 –1 –1
Joachim Johansson 13 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 17 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 13 1 1 1 –1 1 1 1 1 1 1 1 –1 1 1
Mikhail Youzhny 7 4 1 1 –1 –1 1 1 –1 1 1 1 1 1 1 1 1
Tommy Haas 16 18 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1
Nicolas Massu 14 10 1 1 1 –1 –1 –1 1 1 1 1 1 –1 1 1 1 1 1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 1 1 1
Nicolas Kiefer 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1 1 1
328
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.68421053
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 130
z = 4.21775695
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
329
Player
Bradley-
Terry
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 5 1
Safin, Marat 5 14 81
Moya, Carlos 10 11 1
Henman, Tim 9 12 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 9 1
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 13 16 9
Robredo, Tommy 18 17 1
Hrbaty, Dominik 20 15 25
Grosjean, Sebastien 15 13 4
Youzhny, Mikhail 7 4 9
Haas, Tommy 16 18 4
Massu, Nicolas 14 10 16
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 20 1
Total 200
ρ = 0.849624
330
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.849624
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.703425
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the
approximate algorithm of the bayesian solution to the poisson model.
7.7.42 Bradley-Terry Model vs Row Sum Method
1 for agreement and
–1 for disagreement
Brad
ley-Terry
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Bradley-Terry 1 3 4 5 10 9 6 2 8 12 11 13 18 20 15 7 16 14 17 19
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 5 4 1 1 1
Carlos Moya 10 10 1 1 1 1
Tim Henman 9 9 1 1 1 1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 8 12 1 1 1 1 –1 –1 1 1
Gaston Gaudio 12 7 1 1 1 1 –1 –1 1 1 –1
Guillermo Canas 11 8 1 1 1 1 –1 –1 1 1 –1 –1
Joachim Johansson 13 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 18 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 20 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 15 20 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Mikhail Youzhny 7 11 1 1 1 1 –1 –1 1 1 1 –1 –1 1 1 1 1
Tommy Haas 16 15 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 –1 1
Nicolas Massu 14 17 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 –1
Vince Spadea 17 19 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1 1
Nicolas Kiefer 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1 –1 –1 –1
332
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.64210526
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 122
z = 3.95820268
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the row sum
method.
333
Player
Bradley-
Terry
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 3 1
Safin, Marat 5 4 1
Moya, Carlos 10 10 0
Henman, Tim 9 9 0
Coria, Guillermo 6 6 0
Agassi, Andre 2 5 9
Nalbandian, David 8 12 16
Gaudio, Gaston 12 7 25
Canas, Guillermo 11 8 9
Johansson, Joachim 13 16 9
Robredo, Tommy 18 18 0
Hrbaty, Dominik 20 14 36
Grosjean, Sebastien 15 20 25
Youzhny, Mikhail 7 11 16
Haas, Tommy 16 15 1
Massu, Nicolas 14 17 9
Spadea, Vincent 17 19 4
Kiefer, Nicolas 19 13 36
Total 198
ρ = 0.851128
334
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.851128
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.70998
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the Bradley-Terry model and the ranks obtained by the row sum
method.
7.7.43 Poisson Model vs Approx. Algorithm of Bayesian Solution Poisson Model
1 for agreement and
–1 for disagreement
Poisso
n M
odel
Poisso
n Approx
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Roger Federer 1 1
Andy Roddick 3 3 1
Lleyton Hewitt 4 5 1 1
Marat Safin 7 14 1 1 1
Carlos Moya 11 11 1 1 1 –1
Tim Henman 12 12 1 1 1 –1 1
Guillermo Coria 6 6 1 1 1 1 1 1
Andre Agassi 2 2 1 1 1 1 1 1 1
David Nalbandian 8 9 1 1 1 –1 1 1 1 1
Gaston Gaudio 9 7 1 1 1 –1 1 1 1 1 –1
Guillermo Canas 10 8 1 1 1 –1 1 1 1 1 –1 1
Joachim Johansson 17 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 16 17 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 18 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 14 13 1 1 1 –1 1 1 1 1 1 1 1 1 1 1
Mikhail Youzhny 5 4 1 1 –1 1 1 1 1 1 1 1 1 1 1 1 1
Tommy Haas 15 18 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 1 1
Nicolas Massu 13 10 1 1 1 –1 –1 –1 1 1 1 1 1 1 1 1 1 1 1
Vince Spadea 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Nicolas Kiefer 19 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1
336
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.8
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 152
z = 4.9315312
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the poisson model and the ranks obtained by the approximate
algorithm of the bayesian solution to the poisson model.
337
Player
Poisson
Model
Poisson
Approx
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 3 0
Hewitt, Lleyton 4 5 1
Safin, Marat 7 14 49
Moya, Carlos 11 11 0
Henman, Tim 12 12 0
Coria, Guillermo 6 6 0
Agassi, Andre 2 2 0
Nalbandian, David 8 9 1
Gaudio, Gaston 9 7 4
Canas, Guillermo 10 8 4
Johansson, Joachim 17 16 1
Robredo, Tommy 16 17 1
Hrbaty, Dominik 18 15 9
Grosjean, Sebastien 14 13 1
Youzhny, Mikhail 5 4 1
Haas, Tommy 15 18 9
Massu, Nicolas 13 10 9
Spadea, Vincent 20 19 1
Kiefer, Nicolas 19 20 1
Total 92
ρ = 0.930827
338
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.930827
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 4.057381
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the poisson model and the ranks obtained by the approximate
algorithm of the bayesian solution to the poisson model.
7.7.44 Poisson Model vs Row Sum Method
1 for agreement and
–1 for disagreement
Poisso
n M
odel
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Poisson Model 1 3 4 7 11 12 6 2 8 9 10 17 16 18 14 5 15 13 20 19
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 4 3 1 1
Marat Safin 7 4 1 1 1
Carlos Moya 11 10 1 1 1 1
Tim Henman 12 9 1 1 1 1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 8 12 1 1 1 1 –1 –1 1 1
Gaston Gaudio 9 7 1 1 1 1 1 1 1 1 –1
Guillermo Canas 10 8 1 1 1 1 1 1 1 1 –1 1
Joachim Johansson 17 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 16 18 1 1 1 1 1 1 1 1 1 1 1 –1
Dominik Hrbaty 18 14 1 1 1 1 1 1 1 1 1 1 1 –1 –1
Sebastien Grosjean 14 20 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1
Mikhail Youzhny 5 11 1 1 1 –1 –1 –1 –1 1 1 –1 –1 1 1 1 1
Tommy Haas 15 15 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1
Nicolas Massu 13 17 1 1 1 1 1 1 1 1 1 1 1 –1 1 –1 1 1 –1
Vince Spadea 20 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Kiefer 19 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1 1 –1 –1 1
340
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.65263158
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 124
z = 4.02309124
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the poisson model and the ranks obtained by the row sum
method.
341
Player
Poisson
Model
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 4 3 1
Safin, Marat 7 4 9
Moya, Carlos 11 10 1
Henman, Tim 12 9 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 5 9
Nalbandian, David 8 12 16
Gaudio, Gaston 9 7 4
Canas, Guillermo 10 8 4
Johansson, Joachim 17 16 1
Robredo, Tommy 16 18 4
Hrbaty, Dominik 18 14 16
Grosjean, Sebastien 14 20 36
Youzhny, Mikhail 5 11 36
Haas, Tommy 15 15 0
Massu, Nicolas 13 17 16
Spadea, Vincent 20 19 1
Kiefer, Nicolas 19 13 36
Total 200
ρ = 0.849624
342
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.849624
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.703425
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the poisson model and the ranks obtained by the row sum
method.
7.7.45 Approx. Algorithm of Bayesian Solution Poisson Model vs Row Sum
1 for agreement and
–1 for disagreement
Poisso
n Approx
Row Sum M
ethod
Roger F
ederer
Andy Roddick
Lley
ton Hew
itt
Marat S
afin
Carlo
s Moya
Tim
Henman
Guillerm
o Coria
Andre A
gassi
David Nalb
andian
Gasto
n Gaudio
Guillerm
o Canas
Joach
im Jo
hansso
n
Tommy Robred
o
Dominik Hrbaty
Sebastien
Grosjean
Mikhail Y
ouzhny
Tommy Haas
Nico
las Massu
Vince S
padea
Nico
las Kiefer
Poisson Approx 1 3 5 14 11 12 6 2 9 7 8 16 17 15 13 4 18 10 19 20
Row Sum Method 1 2 3 4 10 9 6 5 12 7 8 16 18 14 20 11 15 17 19 13
Roger Federer 1 1
Andy Roddick 3 2 1
Lleyton Hewitt 5 3 1 1
Marat Safin 14 4 1 1 1
Carlos Moya 11 10 1 1 1 –1
Tim Henman 12 9 1 1 1 –1 –1
Guillermo Coria 6 6 1 1 1 –1 1 1
Andre Agassi 2 5 1 –1 –1 –1 1 1 1
David Nalbandian 9 12 1 1 1 –1 –1 –1 1 1
Gaston Gaudio 7 7 1 1 1 –1 1 1 1 1 1
Guillermo Canas 8 8 1 1 1 –1 1 1 1 1 1 1
Joachim Johansson 16 16 1 1 1 1 1 1 1 1 1 1 1
Tommy Robredo 17 18 1 1 1 1 1 1 1 1 1 1 1 1
Dominik Hrbaty 15 14 1 1 1 1 1 1 1 1 1 1 1 1 1
Sebastien Grosjean 13 20 1 1 1 –1 1 1 1 1 1 1 1 –1 –1 –1
Mikhail Youzhny 4 11 1 1 –1 –1 –1 –1 –1 1 1 –1 –1 1 1 1 1
Tommy Haas 18 15 1 1 1 1 1 1 1 1 1 1 1 –1 –1 1 –1 1
Nicolas Massu 10 17 1 1 1 –1 –1 –1 1 1 1 1 1 –1 1 –1 1 1 –1
Vince Spadea 19 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 –1 1 1 1
Nicolas Kiefer 20 13 1 1 1 1 1 1 1 1 1 1 1 –1 –1 –1 –1 1 –1 –1 –1
344
−=
jobject and iobject of rankings twoin thent disagreeme if1
jobject and iobject of rankings twoin theagreement if1a ij
τ =∑
∑
<
<
ji
2
ij
ji
ij
a
a
= 0.57894737
Test of significance based on Kendal’s Tau:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 950
S = 110
z = 3.56887126
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the approximate algorithm of the bayesian solution to the
poisson model and the ranks obtained by the row sum method.
345
Player
Poisson
Approx
Row
Sum
Method
Squared
difference
of the ranks
Federer, Roger 1 1 0
Roddick, Andy 3 2 1
Hewitt, Lleyton 5 3 4
Safin, Marat 14 4 100
Moya, Carlos 11 10 1
Henman, Tim 12 9 9
Coria, Guillermo 6 6 0
Agassi, Andre 2 5 9
Nalbandian, David 9 12 9
Gaudio, Gaston 7 7 0
Canas, Guillermo 8 8 0
Johansson, Joachim 16 16 0
Robredo, Tommy 17 18 1
Hrbaty, Dominik 15 14 1
Grosjean, Sebastien 13 20 49
Youzhny, Mikhail 4 11 49
Haas, Tommy 18 15 9
Massu, Nicolas 10 17 49
Spadea, Vincent 19 19 0
Kiefer, Nicolas 20 13 49
Total 340
ρ = 0.744361
346
nn
d6
13
n
1i
2
i
−−=ρ∑= = 0.744361
Test of significance based on Spearman’s Rho:
H0: There is no association between the two sets of ranks.
H1: There is association between the two sets of ranks.
σ2 = 0.052632
z = 3.244594
α = 0.95
Critical Value = ± 1.96
Reject H0.
At a 5% significance level there is sufficient evidence to say that there is an association
between the ranks obtained by the approximate algorithm of the bayesian solution to the
poisson model and the ranks obtained by the row sum method.
7.7.46 Summary
We note that the tests of significance based on Kendal’s Tau, and that based on Spearman’s
Rho done on all the pairs of models showed evidence to say that there is an association
between all the ranks of the models. We also noted that ranks obtained by our SL-Models have
quite a strong association with some of the other paired comparisons models, as can be seen on
the next page by the summary of all the values of τ and ρ for comparisons between the models.
τ
SL-
Model
Bin SL-
Model
DDic01
Bin SL-
Model
DD01
Bin SL-
Model
Binomial
Poisson B
Binomial
Poisson ML
Bradley-
Terry
Poisson
Model
Poisson
Approx
Row Sum
Method
SL-Model 0.821053 0.8 0.8 0.8421053 0.968421053 0.989474 0.831579 0.694737 0.63157895
Bin SL-Model 0.915789 0.873684 0.7894737 0.831578947 0.831579 0.778947 0.684211 0.74736842
DDic01 Bin SL-Model 0.894737 0.7684211 0.810526316 0.810526 0.778947 0.726316 0.68421053
DD01 Bin SL-Model 0.7263158 0.810526316 0.789474 0.757895 0.705263 0.66315789
Binomial Poisson B 0.852631579 0.852632 0.8 0.663158 0.66315789
Binomial Poisson ML 0.978947 0.8 0.663158 0.64210526
Bradley-Terry 0.821053 0.684211 0.64210526
Poisson Model 0.8 0.65263158
Poisson Approx 0.57894737
Row Sum Method
ρ
SL-
Model
Bin SL-
Model
DDic01
Bin SL-
Model
D01bin
SL-
Model
Binomial
Poisson B
Binomial
Poisson ML
Bradley-
Terry
Poisson
Model
Poisson
Approx
Row Sum
Method
SL-Model 0.95188 0.941353 0.941353 0.9609023 0.993984962 0.998496 0.957895 0.858647 0.84962406
Bin SL-Model 0.978947 0.966917 0.9233083 0.95037594 0.953383 0.912782 0.852632 0.90977444
DDic01 Bin SL-Model 0.972932 0.9112782 0.941353383 0.942857 0.914286 0.887218 0.85864662
DD01 Bin SL-Model 0.8917293 0.942857143 0.93985 0.896241 0.870677 0.83007519
Binomial Poisson B 0.959398496 0.962406 0.944361 0.834586 0.86015038
Binomial Poisson ML 0.996992 0.933835 0.831579 0.84210526
Bradley-Terry 0.95188 0.849624 0.85112782
Poisson Model 0.930827 0.84962406
Poisson Approx 0.7443609
Row Sum Method
349
8 Conclusion
We have found a new model for Paired Comparisons for discrete data. Although it was
designed for the case where the scores have an upper limit to them, the model easily
generalised to the case where the scores do not have a set upper limit to them. In our model
the data we use is the cumulative score of object i out of all the times it was compared to
object j.
An interesting property of our model is that the weights are shift invariant, but the data is
scale invariant. A drawback in our model is that if the data contains too many zeros, then the
weights cannot be shifted so that all the weights are between zero and one i.e. the difference
of the biggest and the smallest weight is more than one, in which case, predictions cannot be
made as not all probabilities pij = 2
pp
2
1
2
p1p jiji −+=
−+ will be between zero and one in
such cases. This occurs mostly in the binary SL-model and sometimes in the DDic01 binary
SL-model.
The binary SL-model was found for the case where we just take into account if an object is
preferred or not i.e. if a team beat or lost to another team. Thus score is xi|j = 1 if object i beat
object j and 0 otherwise. Ties are not possible in a single comparison. As the weights are shift
invariant, if we double all the xi|j, we receive the same weights. We thus followed a practice
in paired comparisons to get rid of zeros in the data, by after doubling all the xi|j’s, making
any xi|j that equals zero into a one if object i competed in at least one game against object j
(i.e. if xi|j = 0 and xj|i ≠ 0), thus yielding the DDic01 binary SL-model. We may need to get
rid of even more of the zeros, thus making not only after doubling all the xi|j’s, any xi|j that
equals zero into a one if object i competed in at least one game against object j, but also if i
and j never competed (were never compared), thus yielding the DDic01 binary SL-model.
All 4 cases of the SL-model showed high association with other PC models. A drawback of
our model however is that the ML estimates we used for the weights of the objects may be
local maximums.
350
9 References
[1] Bain, L.J., Engelhardt, M. 1992. Introduction to Probability and Mathematical Statistics,
Second Edition.
[2] Bock, R.D., Jones, L.V. 1968. The measurement and prediction of judgment and choice.
San Francisco, CA: Holden-Day.
[3] David, H.A., 1963. The method of paired comparisons. Number Twelve of Griffin’s
Statistical Monographs & courses edited by MG Kendall.
[4] Fechner, G.T., 1860. Elemente der Psychophysik. Leipzig: Breitkopf und Hartel.
[5] Hilliard-Lomas, J.L., 1999. Statistical Methods of paired comparisons for discrete
populations. PhD Thesis.
[6] Litvine, I.N., Hilliard-Lomas, J.L., 1996. Bayesian Models for Rugby Tournaments.
Abstracts of the Fourth World Meeting of the International Society for Bayesian Analysis.
Cape Town.
[7] Litvine, I.N., 2004. Models and methods of paired comparisons.
[8] Mosteller, F., 1951. Remarks on the method of paired comparisons: 1.The least squares
solution assuming equal standard deviation and equal correlations. Psychometrica 16.
[9] Rao, P.V., Kupper, L.L., 1967. Ties in paired-comparison experiments: generation of the
Bradley-Terry model. J. Amer. Statist. Assoc. 62.
[10] Remage, R., Jr., Thompson, W.A., Jr 1966. Maximum-likelihood paired comparison
rankings. Biometrica 53.
[11] Reznikova, A.Ya., Shmerling, D.S., 1988. Estimation of parameters of probabilistic
models of binary and multiple comparisons. Plenum Publishing corporation.
[12] Thurstone, L.L., 1927. A law of comparative judgment. Psychol. Rev. 34.
[13] Thurstone, L.L., 1927. Psychophysical analysis. Amer. J. Psychol. 38.
[14] Thurstone, L.L., 1927. The method of paired comparisons for social values. J. Abnorm.
Soc. Psychol. 21.