This paper studies the evolution of peoples' models of how other people think - their theories of mind. First, this is formalized within the level-k model, which postulates a hierarchy of types, such that type k plays a k times iterated best response to the uniform distribution. It is found...

The importance of categorical reasoning in human cognition is well-established in psychology and cognitive science, and it is generally acknowledged that one of the most important functions of categorization is to facilitate prediction. This paper provides a model of optimal categorization. In...

We develop a formal model of social duties. Duties to respect entitlements (duties of justice) differ from duties to promote well-being (duties of charity). A situationspecific version of our model takes entitlements as primitives. A fully portable version derives entitlements from situational...

We develop a framework in which individuals preferences co-evolve with their abilities to deceive others regarding their preferences and intentions. We show that a pure outcome is stable, essentially if and only if it is an efficient Nash equilibrium. All individuals have the same deception...

This paper develops a new theory of community enforcement that explains how cooperation can be sustained when agents change their partners over time. We study environments in which agents are randomly matched to play a Prisoner's Dilemma, and each player observes a few of the partner's past...

In various environments new agents may base their decisions on observations of actions taken by a few other agents in the past. In this paper we analyze a broad class of such social learning processes, and study under what circumstances the initial behavior of the population has a lasting...