In three chapters I study the formation of social networks, and the impact the structures that arise may have in various economic settings. First, I develop a model of social network formation with heterogeneous agents and incomplete information. The model predicts an equilibrium in which agents...

A mechanism that is both efficient and incentive compatible in the Bayesian-Nash sense is shown to be payoff-equilvalent to a Groves mechanism at the point in time when each agent has just acquired his private information. This equilvalence result simplifies the question of whether or not an...