Cooperative behavior and the frequency of social interaction

We report results from an experiment that examines play in an indefinitely repeated, 2-player Prisoner’s Dilemma game. Each experimental session involves N subjects and a sequence of indefinitely repeated games. The main treatment consists of whether agents are matched in fixed pairings or matched randomly in each indefinitely repeated game. Within the random matching treatment, we vary the information that players have about their opponents. Contrary to a theoretical possibility suggested by Kandori (1992), a cooperative norm does not emerge in the treatments where players are matched randomly. On the other hand, in the fixed pairings treatment, the evidence suggests that a cooperative norm does emerge as players gain more experience. JEL Codes: C72, C73, C78, C92, D83 * Funding for this project was provided by the National Science Foundation under grant # SES-0213658. We thank Scott Kinross for excellent research assistance. Email John Duffy: [email protected], Jack Ochs: [email protected]