Conformism and Cooperation in a Local Interaction Model

Mengel, Friederike (2007): Conformism and Cooperation in a Local Interaction Model.

Abstract

We present and analyze a local interaction model where agents play a bilateral prisoner's dilemma game with their neighbors. Agents learn about behavior through payoff-biased imitation of their interaction neighbors (and possibly some agents beyond this set). We find that the [Eshel, I., L. Samuelson and A. Shaked, 1998, Altruists, Egoists and Hooligans in a Local Interaction Model, Am. Econ. Rev 88] result that polymorphic states are stochastically stable in such a setting is not robust. In particular whenever agents use information also of some agents beyond their interaction neighbors the unique stable outcome is one where everyone chooses defection. Introducing a sufficiently strong conformist bias into the imitation process we find that full cooperation always emerges. Conformism is thus identified as a new mechanism that can stabilize cooperation.

• Item Type: MPRA Paper
• Language: English
• Keywords: Cooperation; Imitation; Local Interaction; Conformism
• Subjects: C - Mathematical and Quantitative Methods > C7 - Game Theory and Bargaining Theory > C72 - Noncooperative Games; C - Mathematical and Quantitative Methods > C7 - Game Theory and Bargaining Theory > C73 - Stochastic and Dynamic Games ; Evolutionary Games ; Repeated Games

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