Special workshop on information privacy

Abstract

Over the past decade, social network sites have experienced dramatic growth in popularity. Once a youth-centric phenomena, the use of services like Facebook and Google+ now cross almost all demographics. With this growth, users have been challenged to manage novel privacy hurdles and negotiate nuanced balances between withholding and disclosing personal information. To date, however, no study has documented the evolution of disclosure and privacy behavior on popular social networking sites over an extended period of time. In this manuscript we use actual profile data from a longitudinal panel of 5,076 Facebook users to understand how their disclosure behavior changed between 2005 and 2011. Our findings suggest that 1) Facebook users in our dataset became increasingly protective of their personal information over time, limiting data shared with strangers; 2) changes effected by Facebook over the period of time under our observation, such as interface changes, arrested or in some cases inverted that trend; 3) over time, the amount and scope of personal information that Facebook users reveal to connected “friends” profiles has increased dramatically–but so have the disclosures to “silent listeners” on the network: third-party apps, Facebook itself, and (indirectly) advertisers.