Evolving N-person social dilemma strategies to resolve questions on participation in climate change programs

This paper describes an N-person social dilemma game created to study how climate change agreement strategies develop. The players in this game are trying to collect a target amount for a climate fund. Players fall into three categories: cooperators who contribute their fair share, altruists who contribute more than their fair share and defectors who contribute nothing. In all cases we would evolve a set of player strategies that collected the target sum (-0%/+0.5%). Our results indicate defection is a preferred strategy, but group-level reciprocity or non-altruistic punishment from a third party can dramatically increase levels of cooperation.