  Evolution of cooperation is a widely studied problem in biology, social
science, economics, and artificial intelligence. Most of the existing
approaches that explain cooperation rely on some notion of direct or indirect
reciprocity. These reciprocity based models assume agents recognize their
partner and know their previous interactions, which requires advanced cognitive
abilities. In this paper we are interested in developing a model that produces
cooperation without requiring any explicit memory of previous game plays. Our
model is based on the notion of, a concept introduced within behavioral
economics, whereby individuals care about payoff equality in outcomes. Here we
explore the effect of using income inequality to guide partner selection and
interaction. We study our model by considering both the well-mixed and the
spatially structured population and present the conditions under which
cooperation becomes dominant. Our results support the hypothesis that inequity
aversion promotes cooperative relationship among nonkin.
