7th ieee/acm international conference on advances in social networks analysis and mining privacy...
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy Concerns vs. User Behavior in Community Question Answering
Imrul KayesUSF
Nicolas KourtellisTelefonica Research
Francesco BonchiYahoo Labs
Adriana IamnitchiUSF
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Community Question Answering Sites• CQA sites: Popular platforms– Yahoo Answers: 200M users, 5M users/day– Quora: 1M/month– Stack Exchange: 4M users (e.g., Stack Overflow)
• Functionalities:– Q/A posts & comments, social networking,
leaderboards, and more.• Why do we need them?– Not all web-searches are successful!– Complicated / intricate questions!
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Motivation• Privacy of user data: important but unresolved
issue• Privacy vs. platform usability:– Public content is helpful but users would prefer privacy
• Privacy-aware users are more engaged (e.g., on FB)– Is there a sweet-spot?
Priv
acy
Platform usability
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Main Idea• Utilize users’ modifications on privacy settings
as a proxy of privacy concerns• Group users into privacy categories:
1. Public2. Semi-private• QA-private, Network-private
3. Private• Study users’ engagement vs. privacy concerns– Use activity logs & privacy settings instead of
surveys
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Outline• CQA platforms• Motivation• Main idea• Research Questions• Yahoo Answers Dataset• Results• Proposals for CQA platforms improvements
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Motivating Research Questions
1. Are privacy-concerned users more engaged than public users?– Retention, social circles
2. Do privacy-concerned users contribute differently to the community than public users– Points, best answers
3. Do privacy-concerned users have different perception on answer quality than public users?– Thumbs up/down of best answers
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Motivating Research Questions
4. Are privacy-concerned users also more abuse-conscious?– Abuse reporting
5. Are privacy-concerned users more likely to violate community rules?– Deviance score
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Yahoo Answers Dataset• 1.5M users (2012-2013)– 2.6M follower-followee ties (SN properties*)– LCC: 1.1M nodes (74%), 2.4M edges (92%)
• Keep active users with more than 10 Q/A (68%)• 4 privacy settings:– All public (84.4%), PU– Hide content (Questions/Answers) (2.5%), QA– Hide network (Followers/Followees) (0.9%), N– Hide content & network (12.2%), PR
PublicSemi-PrivatePrivate
*Kayes et al. “The social world of content abusers in Community Question Answering“, WWW’2015
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Retention
• Semi-private users have higher inter-event time• Private users have lower inter-event time
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Social Circles
Indegree = #followers, Outdegree = #followees
• Privacy-concerned users have larger social circles• Followers or followees
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Accomplishments
• Private & semi-private users have more points• Privacy-concerned users contribute more in YA
quantitatively
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Accomplishments
best answer percentage (BAP
• Privacy-concerned users contribute more in YA qualitatively
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Best Answers
• Privacy-concerned users select more Best Answers
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
• Community feedback via thumbs up and down:
• Privacy-concerned users have more average thumbs on Best Answers
Privacy & Best Answer Quality
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Abuse Reporting
• 90% of reports submitted by 8% of users
• Privacy-concerned users post more valid reports
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy & Deviance
• Deviance can indicate user engagement*• Private > semi-private > public users’ deviance scores
* Kayes et al. “The social world of content abusers in community question answering“, WWW’2015
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Summary
1. 87.20% public profiles (default)2. Privacy-concerned users are more engaged:– higher retention– more social network contacts– contribute more & better content– higher perception on answer quality– better citizens in terms of reporting abuses– higher platform engagement (via deviance)
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7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Suggestions for better CQA platforms
• If privacy settings modified:– Likely commitment to the platform– Question recommendation and routing– Community moderation
• If privacy settings unmodified:– Incentivize for increased participation & retention
• Privacy settings in CQA sites– Prediction & recommendation via ML techniques
7th IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Privacy Concerns vs. User Behavior in Community Question Answering
Imrul KayesUSF
Nicolas KourtellisTelefonica Research
Francesco BonchiYahoo Labs
Adriana IamnitchiUSF
Paper: http://arxiv.org/abs/[email protected]
Twitter: @kourtellis