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...

We examine evolutionary basis for risk aversion with respect to aggregate risk. We study populations in which agents face choices between aggregate risk and idiosyncratic risk. We show that the choices that maximize the long-run growth rate are induced by a heterogeneous population in which the...

A strong correlated equilibrium is a strategy profile that is immune to joint deviations. Different notions of strong correlated equilibria were defined in the literature. One major difference among those definitions is the stage in which coalitions can plan a joint deviation: before (ex-ante)...

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...

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...

Abstract A strong correlated equilibrium is a strategy profile that is immune to joint deviations. Different notions of strong correlated equilibria were defined in the literature. One major difference among those definitions is the stage in which coalitions can plan a joint deviation: before...

We examine evolutionary basis for risk aversion with respect to aggregate risk. We study populations in which agents face choices between aggregate risk and idiosyncratic risk. We show that the choices that maximize the long-run growth rate are induced by a heterogeneous population in which the...

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...

Abstract A strong correlated equilibrium is a strategy profile that is immune to joint deviations. Different notions of strong correlated equilibria were defined in the literature. One major difference among those definitions is the stage in which coalitions can plan a joint deviation: before...