CMU Usable Privacy and Security Laboratory Power Strips, Prophylactics, and Privacy, Oh My! Julia Gideon, Serge Egelman, Lorrie Cranor, and Alessandro Acquisti

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Good! Users claim to value privacy Users claim to value privacy More and more are concerned More and more are concerned Top concerns Top concerns Insecure transactions Data sharing Theft of data Lost revenue Lost revenue By 2006, $24.5B lost (Juniper Research, 2002) More online shopping with privacy guarantees More online shopping with privacy guarantees

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Policies Users like notices Users like notices In theory… Rapid adoption Rapid adoption Problems Problems Comprehension Hard to find Lengthy Subject to changing without notice There must be a better way! There must be a better way!

CMU Usable Privacy and Security Laboratory Serge Egelman Platform for Privacy Preferences Project (P3P) Developed by the World Wide Web Consortium (W3C) Developed by the World Wide Web Consortium (W3C) Final P3P1.0 Recommendation issued 16 April 2002 Offers an easy way for web sites to communicate about their privacy policies in a standard machine-readable format Offers an easy way for web sites to communicate about their privacy policies in a standard machine-readable format Can be deployed using existing web servers Enables the development of tools (built into browsers or separate applications) that Enables the development of tools (built into browsers or separate applications) that Summarize privacy policies Compare policies with user preferences Alert and advise users P3P support built into IE6 and Netscape 7 P3P support built into IE6 and Netscape 7

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Bird Free download of beta from Free download of beta from Originally developed at AT&T Labs Released as open source “Browser helper object” for IE6 “Browser helper object” for IE6 Reads P3P policies at all P3P-enabled sites automatically Reads P3P policies at all P3P-enabled sites automatically Bird icon at top of browser window indicates whether site matches user’s privacy preferences Bird icon at top of browser window indicates whether site matches user’s privacy preferences Clicking on bird icon gives more information Clicking on bird icon gives more information

CMU Usable Privacy and Security Laboratory Serge Egelman Chirping bird is privacy indicator

CMU Usable Privacy and Security Laboratory Serge Egelman Red bird indicates mismatch

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy settings

CMU Usable Privacy and Security Laboratory Serge Egelman Why can’t somebody else do it?

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Finder Prototype developed at AT&T Labs, improved and deployed by CUPS Prototype developed at AT&T Labs, improved and deployed by CUPS Multiple search APIs Multiple search APIs Locates P3P policies Locates P3P policies Compares with user’s preferences Compares with user’s preferences Reorders annotated search results Reorders annotated search results Users can retrieve “Privacy Report” similar to Privacy Bird policy summary Users can retrieve “Privacy Report” similar to Privacy Bird policy summary

CMU Usable Privacy and Security Laboratory Serge Egelman But Is It Useful? Do users care about web site privacy? Do users care about web site privacy? Have enough web sites adopted P3P that typical search results contain sites with P3P policies? Have enough web sites adopted P3P that typical search results contain sites with P3P policies? Do users have meaningful choices among privacy policies? Do users understand information provided by Privacy Finder? Do users understand information provided by Privacy Finder? Does Privacy Finder influence online purchasing decisions? Does Privacy Finder influence online purchasing decisions?

CMU Usable Privacy and Security Laboratory Serge Egelman Let’s Find Out! Observe purchase decisions Observe purchase decisions Surveys Surveys 5 Point Likert Between groups Between groups 24 Participants “Shopping Finder” Static pages Multiple products Multiple products No price incentive No price incentive Shipping option Shipping option

CMU Usable Privacy and Security Laboratory Serge Egelman

Privacy Preferences Data sharing  Financial (100% opposed)  Medical (92% opposed)  Non-personal information (33% opposed) Opt-out (96% opposed) Access (96% favor) Marketing  Telephone (92% opposed)  /Postal (88% opposed)

CMU Usable Privacy and Security Laboratory Serge Egelman Medium Preference Level Warn when… Warn when… Site collects health or medical information for analysis or marketing. Site shares health or medical information with others. Site shares financial information with others. Site does not allow me to opt-out from marketing lists. Sites shares personally identifiable information with others. Sites does not allow me to see the information collected on me. But do their actions follow? But do their actions follow?

CMU Usable Privacy and Security Laboratory Serge Egelman Results …not really …not really

CMU Usable Privacy and Security Laboratory Serge Egelman Results Acting on privacy concerns Acting on privacy concerns Privacy Finder helps Green bird purchases Green bird purchases Condoms  Experimental: 8/12  Control: 2/12 Power strips  Experimental: 4/12  Control: 1/12 Red bird purchases Red bird purchases Condoms  Experimental: 1/12  Control: 7/12 Power strips  Experimental: 2/12  Control: 2/12

CMU Usable Privacy and Security Laboratory Serge Egelman Results Product privacy concerns Product privacy concerns Condoms (p < 0.025) Power strips (not significant) Price *may* matter Price *may* matter Lower prices in control group Condoms: $13.96 vs. $12.63 Power strips: $17.04 vs. $16.47

CMU Usable Privacy and Security Laboratory Serge Egelman Exit Survey More concerns with condoms (p < 0.008) More concerns with condoms (p < 0.008) Discreet packaging Credit statement Order history Group differences Group differences Data security (experimental: 50%, control: 0) Misunderstood symbols  50% thought green bird means encryption Experimental concerns addressed by P3P 90% said bird influenced decision

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Information Privacy Reports Privacy Reports Four read them Four could not find them Three were not interested Privacy Policies Privacy Policies One third read them Two read Privacy Report but not policy  Trusted Privacy Finder Birds Birds Five avoided red birds False trust

CMU Usable Privacy and Security Laboratory Serge Egelman Limitations & Future Work More control needed More control needed Evenly distributed birds Trust icons for both groups Click logs Click logs Price information Price information Incentives Result order Trust icon Trust icon Boxes vs. birds

CMU Usable Privacy and Security Laboratory Serge Egelman Privacy Finder

CMU Usable Privacy and Security Laboratory