We develop a theory that explains how and when privacy can increase welfare. Without privacy, some individuals misrepresent their preferences, because they will otherwise be statistically discriminated against. This "chilling effect" hurts them individually, and impairs information aggregation....

I show how irrational ideas and rumors can drive asset prices - not because anyone believes them, but because they are commonly known without being common knowledge. The phenomenon is driven by short-term market participants who are well-informed about the information that others have, and who...

With the goal of maximizing expected gains from trade, this paper analyzes the jointly optimal information structure and mechanism in a bilateral trade setting. The difference in gains from trade between the optimal information structure and first best constitutes the minimal loss due to...