Do People Protect Their Privacy on
Facebook?
Measuring Facebook Privacy
Concerns Indirectly
Group Members
Yousra Javed
Hakim Touati
Melissa Lennon
Agenda
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Background
Problem Statement & Motivation
Methodology
Results
Conclusion & Future Work
Background
Privacy is a very emotionally charged topic for most people.
Invoking this emotional response by explicitly mentioning content
sensitivity leads people to exaggerate their concerns
To reliably research privacy concerns, study questions should be
neutral enough to elicit responses that reflect the true values and
potential actions of the survey takers.
Facebook is the ideal context for this subject
of study because the ongoing privacy
concerns do not seem to make much of an
impression on its millions of users. How do
Facebook users truly feel about their privacy?
Background (Prior Research)
Debatin et al.[3] explored user attitudes toward social networks such
as facebook in their paper Facebook and online privacy: attitudes,
behavior and unintended consequences .
Liu et al.[5] explored the users expectation vs. the reality when
analyzing privacy settings.
Braunstein et al.[1] addresses the fact that privacy is a very
emotionally charged topic for most people. Specifically mentioning
content sensitivity invites exaggerated reporting of concerns. Their
paper Indirect Content Privacy Surveys introduced the indirect
survey method but studied generic objects.
Problem Statement & Motivation
Investigate the privacy language affect on Facebook
subjects through indirect questioning
Indirect survey questions diminish any emotional response
because they do not explicitly mention privacy and security.
We believe Facebook users are less private than what they
state. This might be due to:
§  False perceptions of privacy
§  Lack of awareness about Facebook privacy issues
§  Users' attitude toward social networks
Methodology
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Initial Survey Compilation
Pilot Study
Survey Revision Based on Feedback
Deployment and Data Collection
Data Analysis
Methodology
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Initial Survey Compilation
Indirect Survey
Q 1 and 2 : Frequency of use
Pilot Study
Q 3 and 4 : Frequency of sharing
Survey Revision Based on Feedback Q 5 : Potential for embarrassment
upon content exposure
Q 6 : Importance to the user
Deployment and Data Collection
Q 7 : Content ranking based on
Data Analysis
importance
Direct Survey
Q 1 : Potential financial loss
Q 2 : Potential Embarrassment
Q 3 : Ease of access to data
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Demographics and Westin
Questions
Methodology
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Participants: Students of this
class J
Initial Survey Compilation
Indirect Survey (First) and
Pilot Study
Direct Survey afterwards
Survey Revision Based on Feedback
One week gap
Deployment and Data Collection
Results: Lots of comments!!!
Data Analysis
Methodology
Revised the questions based on
suggestions
Categorized direct questions
Merged the surveys into one
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Three parts: Facebook usage
Facebook privacy
Demographics &Westin
Survey Questions
Initial Survey Compilation
Pilot Study
Survey Revision Based on Feedback
Deployment and Data Collection
Data Analysis
Methodology
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Initial Survey Compilation
Pilot Study
Survey Revision Based on Feedback
Deployment and Data Collection
Data Analysis
Link shared on Facebook
and through emails
34 users completed the 40
question survey
Methodology
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Initial Survey Compilation
Pilot Study
Survey Revision Based on Feedback
Deployment and Data Collection
Data Analysis
Data Analysis
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Comparison between the responses of the direct and
indirect questions for each group of related questions
•  Frequency of use
•  Frequency of sharing
•  Importance to the user
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Content-type ranking based on its direct and indirect
privacy score
•  Indirect Pscore = 1/4( A1+A2+A3+A6)+A4+1/2(A5+A6) [1]
•  Direct Pscore = 1/2(A3+A4)+ 1/4(A1+A2+A3+A4)
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Subject classification using Westin s index criteria and
responses of direct and indirect survey [2]
Results
User Demographics
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Results Cont d…
User Classification
Class
Westin
Indirect
Direct
Fundamentalist
2.94%
0%
0%
Pragmatist
94.11
100%
85.2%
Unconcerned
2.94%
0%
14.8%
Results Cont d…
Content-type ranking based on its direct and indirect
privacyRanking
score
of content types based on privacy score
Indirect Questions
Direct Questions
User stated Ranking
Photos, wall posts, status updates (14 users)
Photos, status updates, wall posts (10 users)
Privacy Score
1.25
0.25
Photos
Status Updates
Content Type
Wall Posts
Results Cont d…
Comparison between the responses of the direct and indirect
questions for each group of related questions
5
Average Average
reported
frequency of use for each content type
Reported Frequency of Use for each Facebook Content Type
0
1
2
Rating
3
4
Indirect
Direct
Photos
Status Updates
Content Type
Wall Posts
Content
Type
Indirect
µ
Direct
µ
P-Value
Photos
4.147059
2.117647
2.413e-09
Status
updates
Wall
posts
3.882353
2.352941
1.110e-06
3.735294
2.235294
6.681e-07
Results Cont d…
Comparison between the responses of the direct and indirect
questions for each group of related questions
Average reported frequency of sharing for each content type
5
Average Reported Frequency of Sharing for each Facebook Content Type
0
1
2
Rating
3
4
Indirect
Direct
Photos
Status Updates
Content Type
Wall Posts
Content
Type
Indirect
µ
Direct
µ
P-Value
Photos
4.823529
2.823529
7.317e-10
Status
updates
Wall
posts
4.088235
2.441176
6.063e-07
4.058824
2.735294
3.671e-05
Results Cont d…
Comparison between the responses of the direct and indirect
questions for each group of related questions
5
AverageAverage
reported
ofFacebook
eachContent
content
type
Reportedimportance
Importance for each
Type
3
Indirect
µ
Direct
µ
P-Value
Photos
4.176471
1.411765
2.2e-16
Status
updates
Wall
posts
2.470588
1.705882
0.01650
3.000000
1.617647
2.572e-05
0
1
Rating
Content
Type
2
4
Indirect
Direct
Photos
Status Updates
Content Type
Wall Posts
Conclusions & Future Work
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What we accomplished
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Built a pilot survey to evaluate users privacy concerns and privacy wording
effect.
Refined the survey questions.
We analyzed the results of our survey.
Users have less perceived usage and sharing habits than in
reality.
Why it is hard to evaluate privacy importance in SN?
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Because it is relative to general privacy.
Because it is relative to content desirability and importance.
Future work will consist of
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Refining the survey questions and adapting them to Facebook and real word
content.
Study the relative privacy importance when compared to real world importance.
References
[1] Alex Braunstein, Laura Granka, Jessica Staddon, Indirect Content
Privacy Surveys: Measuring Privacy Without Asking About It ,
Symposium on Usable Privacy and Security (SOUPS), 2011
[2] Ponnurangam Kumaraguru, Lorrie Faith Cranor, Privacy Indexes: A
Survey of Westin s Studies
http://www.casos.cs.cmu.edu/publications/papers/CMU-ISRI-05-138.pdf
[3] Bernhard Debatin, Jennette P. Lovejoy, Ann-Kathrin Horn M.A.,
Brittany N. Hughes, Facebook and Online Privacy: Attitudes, Behaviors,
and Unintended Consequences
http://onlinelibrary.wiley.com/doi/10.1111/j.1083-6101.2009.01494.x/
full
[4] Emily Christofides, M.Sc., Amy Muise, M.Sc., and Serge Desmarais,
Ph.D, Information Disclosure and Control on Facebook: Are They Two
Sides of the Same Coin or Two Different Processes? ,
[5] Yabing Liu, Krishna P. Gummadi, Balachander Krishnamurthy, Alan
Mislove, Analyzing Facebook Privacy Settings: User Expectations vs.
Reality http://conferences.sigcomm.org/imc/2011/docs/p61.pdf
Questions