helping users with information disclosure decisions: potential for adaptation (iui2013 presentation)
DESCRIPTION
Presentation at IUI2013, Santa Monica. The full paper can be found at http://bit.ly/iui2013fullTRANSCRIPT
Helping Users with Information Disclosure DecisionsPotential for Adaptation
Bart P. KnijnenburgDepartment of Informatics, UC Irvine
Alfred KobsaDepartment of Informatics, UC Irvine
INFORMATION AND COMPUTER SCIENCES
Mobile apps need personal data
Mobile applications often use personalization
This requires personal information- Demographical data (e.g.
age, hobbies, income)
- Contextual data (e.g. app usage, calendar, location)
INFORMATION AND COMPUTER SCIENCES
Justifying disclosure
Privacy problems!Give people control
Privacy calculus:Tradeo! between privacy and expected benefits
Benefits are hard to graspProvide justifications
INFORMATION AND COMPUTER SCIENCES
Justification typesExplain the reason why the information is requested
May prove the legitimacy of the disclosure request
Highlight the benefits of disclosurePrivacy calculus: tip the scales in favor of the benefits
Appeal to the social norm Eschew privacy calculus by conforming to the majority
Previous work: Justifications seem to workOur goal: Find out which one works best
INFORMATION AND COMPUTER SCIENCES
Outline (spoiler alert)Which justification works best?
Actually, “no justification” works best!
Can we do better?We can adapt the justification (and request order) to the user!
What does that give us?A set of implementable heuristics!
How can we extend these findings?Create a fully adaptive system!
INFORMATION AND COMPUTER SCIENCES
Experiment
INFORMATION AND COMPUTER SCIENCES
Experiment
INFORMATION AND COMPUTER SCIENCES
Gender, etc.
Manipulations
Context data first Demographical data first
Location, etc.
Location, etc.
Gender, etc.
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification types
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification typesNone
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification typesNoneUseful for you
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification typesNoneUseful for youNumber of others
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification typesNoneUseful for youNumber of othersUseful for others
INFORMATION AND COMPUTER SCIENCES
Manipulations
5 justification typesNoneUseful for youNumber of othersUseful for othersExplanation
INFORMATION AND COMPUTER SCIENCES
Which one is best?
Which increases disclosure the most?
Which increases satisfaction the most?
INFORMATION AND COMPUTER SCIENCES
0%#
10%#
20%#
30%#
40%#
50%#
60%#
70%#
80%#
90%#
100%#Context#first# Demographics#first# Context#first# Demograpics#first#
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
Results
INFORMATION AND COMPUTER SCIENCES
*"
1"
**"*"
***"*"
*"
0%"
10%"
20%"
30%"
40%"
50%"
60%"
70%"
80%"
90%"
100%"Context"first" Demographics"first" Context"first" Demograpics"first"
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
none" useful"for"you" #"of"others" useful"for"others" explanaDon"
Results
INFORMATION AND COMPUTER SCIENCES
ResultsJustifications are perceived to be helpful
(except “# of others”)
*"
1"
**"*"
***"*"
*"
0%"
10%"
20%"
30%"
40%"
50%"
60%"
70%"
80%"
90%"
100%"Context"first" Demographics"first" Context"first" Demograpics"first"
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
none" useful"for"you" #"of"others" useful"for"others" explanaDon"
***"***"
**"
#1,00"
#0,75"
#0,50"
#0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Perceived(value(of(disclosure(help(
***"***"
**"
#1,00"
#0,75"
#0,50"
#0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Perceived(value(of(disclosure(help(
INFORMATION AND COMPUTER SCIENCES
ResultsJustifications are perceived to be helpful
(except “# of others”)
Higher privacy threat seen for “useful for others”
*"
1"
**"*"
***"*"
*"
0%"
10%"
20%"
30%"
40%"
50%"
60%"
70%"
80%"
90%"
100%"Context"first" Demographics"first" Context"first" Demograpics"first"
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
none" useful"for"you" #"of"others" useful"for"others" explanaDon"
*"
#1,00"
#0,75"
#0,50"
#0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Perceived(privacy(threat(
*"
#1,00"
#0,75"
#0,50"
#0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Perceived(privacy(threat(
INFORMATION AND COMPUTER SCIENCES
ResultsJustifications are perceived to be helpful
(except “# of others”)
Higher privacy threat seen for “useful for others”
Lower trust in the company(esp. “useful for others”)
*"
1"
**"*"
***"*"
*"
0%"
10%"
20%"
30%"
40%"
50%"
60%"
70%"
80%"
90%"
100%"Context"first" Demographics"first" Context"first" Demograpics"first"
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
none" useful"for"you" #"of"others" useful"for"others" explanaDon"
**"1"
$1,00"
$0,75"
$0,50"
$0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Trust&in&the&&company&
**"1"
$1,00"
$0,75"
$0,50"
$0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Trust&in&the&&company&
INFORMATION AND COMPUTER SCIENCES
ResultsJustifications are perceived to be helpful
(except “# of others”)
Higher privacy threat seen for “useful for others”
Lower trust in the company(esp. “useful for others”)
Lower satisfaction
*"
1"
**"*"
***"*"
*"
0%"
10%"
20%"
30%"
40%"
50%"
60%"
70%"
80%"
90%"
100%"Context"first" Demographics"first" Context"first" Demograpics"first"
Disclosure*behavior**
Demographics*disclosure * *Context*disclosure*
none" useful"for"you" #"of"others" useful"for"others" explanaDon"
**" **"***"
1"
$1,00"
$0,75"
$0,50"
$0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Sa#sfac#on)with))the)system)
**" **"***"
1"
$1,00"
$0,75"
$0,50"
$0,25"
0,00"
0,25"
0,50"
0,75"
1,00"
Sa#sfac#on)with))the)system)
INFORMATION AND COMPUTER SCIENCES
Problem!
Justifications did not have the expected e!ects
People liked the help, but:No increase in disclosure (bad for personalization)No decrease in perceived threat, no increase in trust Satisfaction is lower
INFORMATION AND COMPUTER SCIENCES
Idea: Adaptation
I do whatever others do
I care about the benefits
INFORMATION AND COMPUTER SCIENCES
Gender, etc.
Location, etc.
Idea: Adaptation
I am more hesitant about context data
Location, etc.
Gender, etc.
I am more hesitant about demographics
INFORMATION AND COMPUTER SCIENCES
Adapt to what?
Big di!erences in privacy behavior:
3 privacy groups, based on disclosure tendencyPrivacy fundamentalists, pragmatists, and unconcerned
GenderFemales have higher concerns, especially for context data
AgeOlder people have higher concerns, but are also more careful
didn’t work
2 groups, 0-22 items and 23-31 items
INFORMATION AND COMPUTER SCIENCES
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Demographics disclosure- Demographics first,
‘explanation’ justification
Context data disclosure- Context first, no
justification
Heuristics
Overall disclosure: Context first, ‘useful for you’ justification
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Heuristics
Males with low disclosure tendency (73 participants)
Females with low disclosure tendency (88 participants)
Males with high disclosure tendency (150 participants)
Females with high disclosure tendency (178 participants)
Figure 4: The estimated effects of justification type and request order on user satisfaction for each gender and disclosure tendency. Since the outcomes are scale-free factor scores, the y-axis is scaled in sample standard deviations (i.e. 95% of the participants fall
within a 4.0-range), and the value for [male, low disclosure tendency, context first, no justification] is set to zero.
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.045
p=.052
=.009 p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.089
p=023
p=.023
p=.063
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.038
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.009 p=.008 p=.012
p=.097
p=.066
p=.036
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p<.001
p=.026
p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.012 p=.036 p=.036
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.061 p=.045
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p=.011
p=.032
p=.001
p<.001
p=.056
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.060
p=.061
p=.049
p=.032
p=.003
p=.039
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.047
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.032
p=.001 p=.003
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.058
p=.001
p=.074
p=.002
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.025
p=.049 p=.039 p=.059
p=.041
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.039
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
Satisfaction- Context first, ‘explanation’ justification
- Demographics first ‘useful for you’ justification ■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Heuristics -- best compromise
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Males with low disclosure tendency (73 participants)
Females with low disclosure tendency (88 participants)
Males with high disclosure tendency (150 participants)
Females with high disclosure tendency (178 participants)
Figure 4: The estimated effects of justification type and request order on user satisfaction for each gender and disclosure tendency. Since the outcomes are scale-free factor scores, the y-axis is scaled in sample standard deviations (i.e. 95% of the participants fall
within a 4.0-range), and the value for [male, low disclosure tendency, context first, no justification] is set to zero.
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.045
p=.052
=.009 p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.089
p=023
p=.023
p=.063
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.038
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.009 p=.008 p=.012
p=.097
p=.066
p=.036
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p<.001
p=.026
p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.012 p=.036 p=.036
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.061 p=.045
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p=.011
p=.032
p=.001
p<.001
p=.056
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.060
p=.061
p=.049
p=.032
p=.003
p=.039
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.047
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.032
p=.001 p=.003
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.058
p=.001
p=.074
p=.002
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.025
p=.049 p=.039 p=.059
p=.041
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.039
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Heuristics
Males with low disclosure tendency (73 participants)
Females with low disclosure tendency (88 participants)
Males with high disclosure tendency (150 participants)
Females with high disclosure tendency (178 participants)
Figure 4: The estimated effects of justification type and request order on user satisfaction for each gender and disclosure tendency. Since the outcomes are scale-free factor scores, the y-axis is scaled in sample standard deviations (i.e. 95% of the participants fall
within a 4.0-range), and the value for [male, low disclosure tendency, context first, no justification] is set to zero.
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.045
p=.052
=.009 p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.089
p=023
p=.023
p=.063
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.038
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.009 p=.008 p=.012
p=.097
p=.066
p=.036
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p<.001
p=.026
p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.012 p=.036 p=.036
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.061 p=.045
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p=.011
p=.032
p=.001
p<.001
p=.056
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.060
p=.061
p=.049
p=.032
p=.003
p=.039
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.047
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.032
p=.001 p=.003
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.058
p=.001
p=.074
p=.002
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.025
p=.049 p=.039 p=.059
p=.041
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.039
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Heuristics
Males with low disclosure tendency (73 participants)
Females with low disclosure tendency (88 participants)
Males with high disclosure tendency (150 participants)
Females with high disclosure tendency (178 participants)
Figure 4: The estimated effects of justification type and request order on user satisfaction for each gender and disclosure tendency. Since the outcomes are scale-free factor scores, the y-axis is scaled in sample standard deviations (i.e. 95% of the participants fall
within a 4.0-range), and the value for [male, low disclosure tendency, context first, no justification] is set to zero.
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.045
p=.052
=.009 p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.089
p=023
p=.023
p=.063
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.038
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.009 p=.008 p=.012
p=.097
p=.066
p=.036
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p<.001
p=.026
p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.012 p=.036 p=.036
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.061 p=.045
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p=.011
p=.032
p=.001
p<.001
p=.056
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.060
p=.061
p=.049
p=.032
p=.003
p=.039
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.047
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.032
p=.001 p=.003
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.058
p=.001
p=.074
p=.002
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.025
p=.049 p=.039 p=.059
p=.041
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.039
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Figure 3: The effects of justification type and request order on disclosure (for each type of data, gender, and disclosure tendency).
Error bars are ±1 standard error. The best strategy is labeled with an arrow; strategies with a p-value perform significantly worse.
Demograhics data! Context data!
46%!p < .001!
69%!p < .001!
53%!p < .001! 48%!
p < .001!
57%!p < .001!
67%!
45%! p = .079!35%!
42%! 46%!
87%!p = .057!
67%!p = .003!
80%!p = .003!
90%! 98%!
30%!p = .055!
29%!p = .076!
30%!p = .054!
P = .002!!
17%!
P = .004!!
14%!no!
justification!useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with low disclosure tendency (73 participants)!
Demograhics data! Context data!
66%!!
p = .005!
60%!p < .001!
58%!p < .001! 48%!
p < .001!
64%!p < .001!
46%! 51%!40%!
47%! 51%!
57%!p = .027!
81%!
89%!
79%! 75%!
p = .010!!
23%!p < .001!
!11%!
p < .001!!
20%!
p = .009!!
27%! 36%!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with low disclosure tendency (88 participants)!
Demograhics data! Context data!
95%!p = .012!
97%!p = .055!
95%!p = .014!
98%!p = .099! 93%!
p = .002!
78%!p = .055! 78%! 88%! 87%! 76%!
p = .041!
99%! 98%! 97%!!
p = .063!
100%! 99%!
82%! 85%!80%!
70%!p = .004!
72%!p = .014!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Males with high disclosure tendency (150 participants)!
Demograhics data! Context data!
95%!p = .029! 91%!
p = .002!92%!
p = .001!96%!
p = .046!96%!
p = .069!
88%! 86%! 71% !p = .003!
83%! 84%!99%! 99%! 96% !
!
p = .049!
99%! 95% !p = .024!
71%!p = .004!
75%!p = .016! 65%!
p < .001!68%!
p = .001!
75%!p = .018!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
no!justification!
useful!for you!
number !of others!
useful for!others!
expla-!nation!
0%!10%!20%!30%!40%!50%!60%!70%!80%!90%!
100%!
Dis
clos
ure
prob
abili
ty!
Females with high disclosure tendency (178 participants)!
Heuristics
Males with low disclosure tendency (73 participants)
Females with low disclosure tendency (88 participants)
Males with high disclosure tendency (150 participants)
Females with high disclosure tendency (178 participants)
Figure 4: The estimated effects of justification type and request order on user satisfaction for each gender and disclosure tendency. Since the outcomes are scale-free factor scores, the y-axis is scaled in sample standard deviations (i.e. 95% of the participants fall
within a 4.0-range), and the value for [male, low disclosure tendency, context first, no justification] is set to zero.
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.045
p=.052
=.009 p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.089
p=023
p=.023
p=.063
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.038
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.009 p=.008 p=.012
p=.097
p=.066
p=.036
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p<.001
p=.026
p=.006
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.012 p=.036 p=.036
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.061 p=.045
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p<.001
p=.011
p=.032
p=.001
p<.001
p=.056
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.060
p=.061
p=.049
p=.032
p=.003
p=.039
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.047
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.032
p=.001 p=.003
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!
2,0!Perceived disclosure help!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.058
p=.001
p=.074
p=.002
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Perceived privacy threat!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.025
p=.049 p=.039 p=.059
p=.041
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!
1,5!Trust in the company!
no!just.!
useful!for you!
# of!othrs!
usef. for
othrs!expl.!
p=.039
-2,0!
-1,5!
-1,0!
-0,5!
0,0!
0,5!
1,0!Satisfaction!
■ Demographics first ● Context first
INFORMATION AND COMPUTER SCIENCES
Following the heuristics
How to discover gender? - Can just be the first item to request
- Highest disclosure rate of all items in our study (94.9%)
How to discover disclosure tendency?- Make some (potentially invasive) requests (not desirable)
- Ask about (or otherwise determine) stated privacy concerns, mobile Internet usage and/or tech-savvyness
INFORMATION AND COMPUTER SCIENCES
Future work
Test the heuristics in a real systemAnd not just an app recommender
Find the rationale behind the heuristicsE.g. why do males and females require di!erent justifications?
Make the system even more adaptive- Select the optimal justification for each item
- Order the requests dynamically to ensure the highest possible disclosure (without reducing satisfaction)
INFORMATION AND COMPUTER SCIENCES
Conclusion (you already know this)Which justification works best?
Actually, “no justification” works best!
Can we do better?We can adapt the justification (and request order) to the user!
What does that give us?A set of implementable heuristics!
How can we extend these findings?Create a fully adaptive system!
Thank [email protected] :: www.usabart.nl :: @usabart