This paper deploys a novel experiment to compare four theories that explain both selfish and non-selfish cooperation. The four theories capture incomplete information (à la Kreps et al. (1982)) alongside the following four non-selfish motives: caring about others (Altruism), being conscientious...

We aim to understand the role and evolution of beliefs in the indefinitely repeated prisoner's dilemma (IRPD). To do so, we elicit beliefs about the supergame strategies chosen by others. We find that heterogeneity in beliefs and changes in beliefs with experience are central to understanding...

We construct an uncoupled randomized strategy of repeated play such that, if every player follows such a strategy, then the joint mixed strategy profiles converge, almost surely, to a Nash equilibrium of the one-shot game. The procedure requires very little in terms of players' information about...

We characterize belief-free equilibria in infinitely repeated games with incomplete information with N \ge 2 players and arbitrary information structures. This characterization involves a new type of individual rational constraint linking the lowest equilibrium payoffs across players. The...

We study the perfect type-contingently public ex-post equilibrium (PTXE) of repeated games with incomplete information where players observe imperfect public signals of the actions and the map from actions to signal distributions is itself unknown. The PTXE payoffs when players are patient are...

Imperfect private monitoring in an infinitely repeated discounted Prisoner’s Dilemma played on a communication network is studied. Players observe their direct neighbors’ behavior only, but communicate strategically the repeated game’s history throughout the network. The delay in receiving...

In this paper we model an evolutionary process with perpetual random shocks, where individuals sample population-specific strategy and payoff realizations and imitate the most successful behavior. For finite n-player games we prove that in the limit, as the perturbations tend to zero, only...

We illustrate one way in which a population of boundedly rational individuals can learn to play an approximate Nash equilibrium. Players are assumed to make strategy choices using a combination of imitation and innovation. We begin by looking at an imitation dynamic and provide conditions under...