designing incentive systems for truthful information sharing · 2 45 0 0 45 product 1 actual demand...
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Designing incentive systems for truthful information
sharing
Ulrich W. Thonemann
New Directions Seminar
Stanford University
April 25, 2013
Based on joint work with Lisa Scheele (University of Cologne) and Marco Slikker (Eindhoven
University of Technology). The authors gratefully acknowledge the support of the Deutsche
Forschungsgemeinschaft through the research group “Design and Behavior.”
Ulrich W. Thonemann (University of Cologne)
AGENDA
1
Motivation
Model
Laboratory Experiment
Validation
Discussion
Ulrich W. Thonemann (University of Cologne)
FORECAST INFLATION AT PHARMACEUTICAL COMPANY Forecast vs. demand in thousand units
2
45
0
45 0
Product 1
Actual demand
Dem
and fore
cast
70
0
70 0
Product 2
120
0
120 0
Product 3 Product 4 75
0
75 0 Actual demand Actual demand
Actual demand D
em
and
fore
cast
Dem
and
fore
cast
Dem
and
fore
cast
Average demand
forecast inflation:
16 %
Over-forecasting
Under-forecasting
Forecast = 20
Demand = 10
Ulrich W. Thonemann (University of Cologne)
SECOND EXAMPLE SUPPORTS DATA OF FIRST EXAMPLE
3
Forecast bias High Low
Forecast error Low High
Demand ≈ 200
Forecast ≈ 900
System forecast
Log-scale
Sales force forecast
Ulrich W. Thonemann (University of Cologne)
TYPICAL INCENTIVE SYSTEM STRUCTURE
Sales 8%
Profit
30%
Qualitative
objectives
Revenues 30%
32%
Market share
Operations
7%
Stock levels
30% Profit
53% Qualitative
Objectives
Service level
3%
Others
7%
Department
CASE EXAMPLE
Ulrich W. Thonemann (University of Cologne)
INCENTIVE SYSTEMS OF SALES
5
Sales-bonus-only
Absolute forecast error
Differentiated forecast error
Forecast error not penalized
Incentive system often used in practice
Absolute deviation of forecast from demand penalized
Incentive system is based on MAD and used in practice
Over-forecasting harder penalized then under-forecasting
Incentive system not/hardly used in practice
Ulrich W. Thonemann (University of Cologne)
AGENDA
6
Motivation
Model
Laboratory Experiment
Validation
Discussion
Ulrich W. Thonemann (University of Cologne)
Sales Operations
GENERAL SETTING
7
Market demand d
= Market condition f
+ Market uncertainty e
Sales observes
market
condition f
(e.g., 100)
Sales sends
forecast of market
condition f
(e.g., 120)
^
Operations
estimates
market
condition
based on f,
m(f| f)
^
^
Operations
determines
order
quantity q
Demand d = f + e
is realized and
min(q, d) is sold
Sales and operations
receive their
compensations
Sales Operations
Ulrich W. Thonemann (University of Cologne)
E[sales bonus]
Order q
Sales bonus
E[forecast penalty]
f ^ Forecast f
Over-forecasting
penalty Under-forecasting
penalty
𝜋𝑆 𝑞,𝜙 𝜙 = 𝐶𝑆 + 𝑏𝐸 min(𝐷, 𝑞) − 𝑝𝑜𝐸 𝜙 − 𝐷+
− 𝑝𝑢𝐸 𝐷 − 𝜙 +
PAYOFF FUNCTION OF SALES
8
Fixed
Incentive systems
Sales-bonus-only (common practice): po = pu = 0
Absolute forecast error (recommended by practitioners): po = pu > 0
Differentiated forecast error (new): po > pu ≥ 0
Total
Ulrich W. Thonemann (University of Cologne)
HOW ARE THE ELEMENTARY OUTCOMES EVALUATED?
9
Mr. A and Mr. B work for the sales division of a company. At the beginning of each month,
Mr. A and Mr. B must provide a demand forecast for the following month. At the end of the
month, they both receive a fixed compensation and a performance-based compensation.
Last month, Mr. A provided a demand forecast of 1,500 units, demand was 1,000 units,
and 1,000 units were sold. He receives a 100 euro sales bonus for the sold quantity in
addition to his regular salary.
Mr. B also provided a demand forecast of 1,500 units, demand was 1,000 units, and
1,000 units were sold. He receives a 150 euro sales bonus for the sold quantity, minus a
50 euro penalty for the deviation of the demand forecast from the actual demand, that is,
Mr. B also receives 100 euro in addition to his regular salary.
Who is happier? Mr. A (40), Mr. B (1), no difference (7).
Sales bonus Fixed Forecasting penalty
𝜋𝑆 𝑞,𝜙 𝜙 = 𝐶𝑆 + 𝑏𝐸 min(𝐷, 𝑞) − 𝑝𝑜𝐸 𝜙 − 𝐷+
− 𝑝𝑢𝐸 𝐷 − 𝜙 +
A: CS + 100 = CS + 100 – 0
B: CS + 100 = CS + 150 – 50
Total
Ulrich W. Thonemann (University of Cologne)
Fixed
Fixed
Underage
cost
Overage
cost
„Lying“ Forecast error penalty Sales bonus
Loss aversion
EXPECTED UTILITY FUNCTIONS
10
𝑢𝑆 𝑞, 𝜙 𝜙 = 𝐶𝑆 + 𝑏𝐸 min(𝐷, 𝑞) − 𝛾𝐸 𝑝𝑜 𝜙 − 𝐷+
− 𝑝𝑢 𝐷 − 𝜙 +
− 𝛽 𝜙 − 𝜙 Sales
Loss aversion Lying aversion
Operations 𝑢𝑂 𝑞 = 𝐶𝑂 − 𝛾𝐸 𝑐𝑜 𝑞 − 𝐷 + + 𝑐𝑢 𝐷 − 𝑞 +
Ulrich W. Thonemann (University of Cologne)
PERFECT BAYESIAN EQUILIBRIUM
11
Theorem 1 For sufficiently large 𝑝𝑜, there exists a separating equilibrium with
𝜙 = 𝜙 + 𝛿 (i) signaling strategy of sales
𝑞 = 𝜙 − 𝛿 + 𝐺−1 ∝ (iii) ordering policy of operations
𝜙 = 𝜙 − 𝛿 (ii) believe update of operations
and distortion factor
𝛿 =
> 0 for 𝑝𝑜 < 2𝑏 1 − 𝛼 − 𝛽
𝛾+ 𝑝𝑢
0 for 2𝑏 1 − 𝛼 − 𝛽
𝛾+ 𝑝𝑢 ≤ 𝑝𝑜 ≤ 2
𝑏 1 − 𝛼 + 𝛽
𝛾+ 𝑝𝑢
< 0 for 2𝑏 1 − 𝛼 + 𝛽
𝛾+ 𝑝𝑢 < 𝑝𝑜.
Corollary 1 For (reasonable values of) 𝛽 < 𝑏 1 − 𝛼 the absolute forecast error
incentive systems incentivizes demand forecast inflation
Note: γ = loss aversion factor, β = lying aversion
Ulrich W. Thonemann (University of Cologne)
AGENDA
12
Motivation
Model
Laboratory Experiment
Validation
Discussion
Ulrich W. Thonemann (University of Cologne)
TREATMENTS
Production incentives at 𝑐𝑢 = 10 and 𝑐𝑜 = 10 (implies critical ratio α = 0.5)
Market condition normally distributed with Φ ∼ 𝒩 100,30
Market uncertainty normally distributed with Ε ∼ 𝒩 0,30
13
16/0/0
14/3/3
12/7/7
10/10/10
Treatment
b/po/pu
10/6/4
10/8/2
10/10/0
10/12/2
8
8
8
8
Periods
8
8
8
8
Experiment Incentive system
Experiment 1 Sales-bonus-only
Absolute forecast error
Absolute forecast error
Absolute forecast error
Experiment 2 Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
Subjects
32
32
Ulrich W. Thonemann (University of Cologne)
MODEL FIT
Model 1
Loglike
BIC
-3,533
7,107
μ𝛾
μ𝛽
3.174 (0.372)
2.199 (0.504)
Model 2 Model 3
-3,595
7,210
-3,797
7,615
4.380 (0.479)
5.870 (0.223)
Note: Standard errors reported in parentheses
14 Note: γ = loss aversion factor, β = lying aversion
Ulrich W. Thonemann (University of Cologne)
AGGREGATE RESULTS
15
∝=𝑐𝑢
𝑐𝑜 + 𝑐𝑢= 0.5 Note: Critical ratio in our experiments
16/0/0
14/3/3
12/7/7
10/10/10
Treatment
b/po/pu
10/6/4
10/8/2
10/10/0
10/12/2
n/a
n/a
44.0
20.2
Standard
model
38.4
15.7
0.0
0.0
Experiment Incentive system
Experiment 1 Sales-bonus-only
Absolute forecast error
Absolute forecast error
Absolute forecast error
Experiment 2 Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
n/a
20.4
6.5
3.3
0.0
-5.5
-22.5
-15.3
Behavioral
model
Average forecast inflation
13.3
6.9
3.9
1.2
-8.4
-16.7
-14.8
Actual
40.7
Ulrich W. Thonemann (University of Cologne)
TREATMENT 12/7/7
16
Market condition
Average
inflation: 6.9
0
50
100
150
200
0 50 100 150 200
Demand forecast
Behavioral model
Standard model
Demand forecast
Average
correction: 3.9 0
50
100
150
200
0 50 100 150 200
Order quantity
Ulrich W. Thonemann (University of Cologne)
Demand forecast
Average
correction: -12.3 0
50
100
150
200
0 50 100 150 200
Order quantity
TREATMENT 10/10/0
17
Market condition
Average
inflation: -17.7
0
50
100
150
200
0 50 100 150 200
Demand forecast
Behavioral model
Standard model
Ulrich W. Thonemann (University of Cologne)
OVERVIEW OF RESULTS OF MAIN EXPERIMENT
18
Significances of differences between model predictions and actual averages (Wilcoxon signed-rank test): *** p < 0.01, ** p < 0.05, * p < 0.1
16/0/0
14/3/3
12/7/7
10/10/10
Treatment
b/po/pu
10/6/4
10/8/2
10/10/0
10/12/2
n/a
n/a
44.0
20.2
Standard
model
38.4
15.7
0.0
0.0
40.7
13.3
6.9
3.9
Actual average
1.2
-8.4
-16.7
-14.8
Forecast distortion ϕ − ϕ
n/a
n/a
-44.0
-20.2
Standard
model
-38.4
-15.7
0.0
0.0
-38.9
-15.4
-3.9
1.0
Actual
average
3.2
7.1
12.3
11.6
Forecast correction q − ϕ
n/a
20.4
6.5
3.3
Behavioral
model
0.0
-5.5
-22.5
-15.3
n/a
-20.4
-6.5
-3.3
Behavioral
model
0.0
5.5
22.5
15.3
***
***
**
***
***
***
***
***
***
***
***
***
***
***
***
Ulrich W. Thonemann (University of Cologne)
AGENDA
19
Motivation
Model
Laboratory Experiment
Validation
Discussion
Ulrich W. Thonemann (University of Cologne)
INCENTIVE SYSTEM DESIGN FOR TRUTHTELLING FORECASTING
Model 1
3.174 (0.372)
2.199 (0.504)
2𝑏 1−𝛼 −𝛽
𝛾+ 𝑝𝑢 ≤ 𝑝𝑜 ≤ 2
𝑏 1−𝛼 +𝛽
𝛾+ 𝑝𝑢 Theorem 1 Truthtelling solution (δ = 0):
Examples b = 10 / po = 12 / pu = 10 and 10/7/5
μ𝛾
μ𝛽
2𝑏/2−2.199
3.174+ 𝑝𝑢 ≤ 𝑝𝑜 ≤ 2
𝑏/2+2.199
3.174+ 𝑝𝑢
Note: γ = loss aversion factor, β = lying aversion
Ulrich W. Thonemann (University of Cologne)
RESULTS OF VALIDATION EXPERIMENT
21
0
50
100
150
200
0 50 100 150 200
Demand forecast
Market condition
Treatment 10/12/10
Average
inflation -0.2
0
50
100
150
200
0 50 100 150 200
Order quantity
Demand forecast
Average
correction -1.6
0
50
100
150
200
0 50 100 150 200
Demand forecast
Market condition
Treatment 10/7/5
Average
inflation +3.6
Order quantity
200
150
100
50
0
200 150 100 50 0
Demand forecast
Average
correction -2.9
Ulrich W. Thonemann (University of Cologne)
AGENDA
22
Motivation
Model
Laboratory Experiment
Validation
Discussion
Ulrich W. Thonemann (University of Cologne)
SUMMARY
23
Proposed including forecast error penalties in incentive system of sales
Developed and tested behavioral model for forecasting and ordering behavior
Showed that forecasts are always inflated under absolute forecast error incentive system
Showed that truthful information sharing can be achieved by differentiated forecast error
incentive system
Next: Validation at pharmaceutical company
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
11 10 09 08 06 05 04 03 02 01 12 11 10 09 08 07 06 05 04 03 02 01 12 07 12 11 10 09 08 07 06 05 04 03 02 01
-5.9
Forecast accuracy included
in sales managers
performance review at 5 %
weight since January 2010
Inflated demands
Percentage of SKUs
2008 2009 2010
Ulrich W. Thonemann (University of Cologne)
OUTLOOK
24
Designing incentive systems for truthful information
sharing
Ulrich W. Thonemann
New Directions Seminar
Stanford University
April 25, 2013
Based on joint work with Lisa Scheele (University of Cologne) and Marco Slikker (Eindhoven
University of Technology). The authors gratefully acknowledge the support of the Deutsche
Forschungsgemeinschaft through the research group “Design and Behavior.”
Ulrich W. Thonemann (University of Cologne)
MODEL FIT
26 Note: γ = loss aversion factor, β = lying aversion
Ulrich W. Thonemann (University of Cologne) 27
HUMAN VS. SYSTEM-GENERATED FORECASTS Share of SKUs per year with forecast > sales, in percent
SOURCE: Data of anonymous pharmaceutical company
CASE EXAMPLE
+3.6 pp +3.9 pp
2010
53,6 49,9
2009
55,4 51,5
Business unit 1 Business unit 2
+6.7 pp +5.6 pp
2010
58,2
51,5
2009
57,3 51,7
Human
System
Ulrich W. Thonemann (University of Cologne)
DESIGN OF EXPERIMENT AND AGGREGATE RESULTS
28
∝=𝑐𝑢
𝑐𝑜 + 𝑐𝑢= 0.5 Note: Critical ratio in our experiments
16/0/0
14/3/3
12/7/7
10/10/10
Treatment
b/po/pu
10/6/4
10/8/2
10/10/0
10/12/2
n/a
n/a
44.0
20.2
Standard
model
38.4
15.7
0.0
0.0
Experiment Incentive system
Experiment 1 Sales-bonus-only
Absolute forecast error
Absolute forecast error
Absolute forecast error
Experiment 2 Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
Differentiated forecast error
n/a
20.4
6.5
3.3
0.0
-5.5
-22.5
-15.3
40.7
13.3
6.9
3.9
1.2
-8.4
-16.7
-14.8
Behavioral
model Actual
Forecast inflation
Ulrich W. Thonemann (University of Cologne) 29
Ulrich W. Thonemann (University of Cologne)
SALES BONUS ONLY INCENTIVE SYSTEM: TREATMENT 16/0/0
30
0
50
100
150
200
0 50 100 150 200
Demand forecast
0
50
100
150
200
0 50 100 150 200
Order quantity
Market condition Demand forecast
Average
inflation: 40.7
Average
correction: 38.9
Behavioral model
Standard model (n.a.)
Ulrich W. Thonemann (University of Cologne) 31