Understanding and supporting selective sharing [electronic resource]

Online social platforms provide a single interface for simultaneously managing relationships from many parts of our lives. Placing these relationships into a single context enables us to manage more connections than ever before, but the challenges associated with addressing multiple, overlapping groups within a single context can be overwhelming. When it becomes to difficult to show our 'best face' to each of these groups, we may end up sharing too little, or perhaps, far too much. Many of these platforms provide mechanisms for selective sharing, or sharing information with subsets of our audience. Despite widespread awareness of these mechanisms and concerns about privacy and identity management, however, many individuals sharing online still fail to use them. This dissertation seeks to expand our understanding of when and how these mechanisms for selective sharing are adopted. Characterizing selective sharing as a set of goal-oriented possibilities for action, I study sharing behavior in three very different social platforms -- Tumblr, Google+, and Flickr -- in order to unravel how individual goals and strategies for action interact to shape selective sharing practices. In the first study, I show how members' goals for platform participation relate to their adoption of selective sharing practices on Tumblr. Using exploratory factor analysis, I identify six motivations for Tumblr use and develop models illustrating their relationship to the adoption of various strategies for selective sharing, including the creation of multiple blogs. For example, I find that individuals for whom blogging is motivated by a desire to support others are more likely to create multiple blogs while making their identity visible across blogs. These findings highlight how different motivations for platform use can lead members to leverage available mechanisms to accomplish different goals. In the next study, I shift focus to individuals motivated to engage in selective sharing, in order to identify the factors which guide their sharing decisions. Through a study of early adopters of Google+, I explore how individuals utilize 'Circles' to engage in audience management and selective disclosure of information. These findings extend the literature on boundary regulation processes by identifying specific considerations which guide individuals to limit or extend access to shared content. The final study illustrates how these observations can help us in modeling individual sharing decisions. Studying the use of permissions settings on Flickr, we develop a model capturing member characteristics and content features to predict permissions for individual photos with 73% accuracy, better than individuals guessing the settings applied to their own recently-uploaded photos. This model illustrates how the access-limiting and access- extending considerations involved in boundary regulation processes can be quantified and applied to the design of systems which provide support for sharing decisions. Taken together, the findings from this dissertation point to a future where sharing systems are neither too simple to be useful or too complex to be used, but rather meet the user halfway to encourage safer and more effective online social participation.

Advisor: Heer Jeffrey Michael
Bernstein Michael S.
Hancock Jeff advisor. Thesis advisor
Shamma David Ayman advisor. Thesis advisor