A novel facet of privacy concern has emerged due to peer disclosure of sensitive personal information in online social communities. When online users post about their “friends” or even “non-friends”, their behavior impose a negative externality on other people.

Professor Hong XU will talk about the use of game theory to analyze interactions among users in social communities. The model encompasses the benefit from posting information, positive externalities such as recognition and entertainment benefits due to others’ sharing of information, and heterogeneous privacy preferences. She will also discuss two policy instruments--nudging and quota--and a combination of the two.