Date of Original Version
Abstract or Description
Data aggregators collect large amounts of information about individual users from multiple sources, and create detailed online behavioral profiles of individuals. Behavioral profiles benefit users by improving products and services. However, they have also raised privacy concerns. To increase transparency, some companies are allowing users to access their behavioral profiles. In this work, we investigated behavioral profiles of users by utilizing these access mechanisms. Using in-person interviews (n=8), we analyzed the data shown in the profiles and compared it with the data that companies have about users. We elicited surprises and concerns from users about the data in their profiles, and estimated the accuracy of profiles. We conducted an online survey (n=100) to confirm observed surprises and concerns. Our results show a large gap between data shown in profiles and data possessed by companies. We also find that large number of profiles contain inaccuracies with levels as high as 80%. Participants expressed several concerns including collection of sensitive data such as credit and health information, extent of data collection and how their data may be used.