We study impersonal exchange and ask how agents can behave honestly in anonymous transactions without contracts. We analyze repeated anonymous random matching games, where agents observe only their own transactions. Little is known about cooperation in this setting beyond the prisoner's dilemma....

Bayesian Nash equilibria that fail to be hindsight-(or, alternatively, ex-post) stable do not provide reliable predictions of outcomes of games in many applications. We characterize a family of large Bayesian games (with many players) in which all equilibria are asymptotically hindsight-stable,...

We examine a model of a monopolist selling to two segments of consumers with different preferences for quality. We show that if the firm is unable to price discriminate between the segments, then there is less investment in quality. We find that both consumer segments, and society overall, may...