Heterogeneous Strategy Learning in the Iterated Prisoner’s Dilemma

Abstract

Axelrod’s work on the prisoner’s dilemma is one of the most discussed models of social cooperation. While many aspects of his computer simulations have been debated, their evolutionary mechanism has not yet received the same attention. We know people do not differ only in the way they act, but also in how they change their behavior – some may like safe routines, others risk with the new. Yet in formal models cultural evolution is taken to be an homogeneous process, such as the imitation of successful peers. In this paper we challenge this view and we propose an agent-based model that takes into account heterogeneity among individuals’ learning strategies. The evolutionary dynamic is an adaptation of the so-called consumat approach, originally developed by Wander Jager and Marco Janssen in order to integrate different models of individuals behavior.