Reducing the Heterogeneity of Payoffs: an Effective Way to Promote Cooperation in Prisoner's Dilemma Game

TL;DR

This study demonstrates that regulating payoff heterogeneity with an optimal strength significantly enhances cooperation in the Prisoner's Dilemma by enlarging cooperator clusters, with implications for understanding cooperative behavior.

Contribution

It introduces a novel payoff regulation method that optimally promotes cooperation by controlling payoff heterogeneity and cluster formation.

Findings

Optimal regulation strength maximizes cooperation.

Cooperators tend to form clusters rather than isolated individuals.

Enlarging cooperator clusters is key to promoting cooperation.

Abstract

In this paper, the total payoff of each agent is regulated to reduce the heterogeneity of the distribution of the total payoffs. It is found there is an optimal regulation strength where the fraction of cooperation is prominently promoted, too weak or too strong of the strength will have little effects or result in the disappearance of the cooperators. It is also found that most of the cooperators are not distributed in isolation but form the cooperator clusters, and to promote the cooperation the only way is to enlarge the size of the cooperator clusters. Finally, we try to explain the emergence of larger clusters and prove the existence of the optimal regulation strength. Our works provide insight into the understanding of the relations between the distribution of payoffs and the cooperative behaviors.