Natural selection and social preferences.
A large number of individuals are randomly matched into groups, where each group plays a finite symmetric game. Individuals breed true. The expected number of surviving offspring depends on own material payoff, but may also, due to cooperative breeding and/or reproductive competition, depend on the material payoffs to other group members. The induced population dynamic is equivalent with the replicator dynamic for a game with payoffs derived from those in the original game. We apply this selection dynamic to a number of examples, including prisoners' dilemma games with and without a punishment option, coordination games, and hawk-dove games. For each of these, we compare the outcomes with those obtained under the standard replicator dynamic. By way of a revealed-preference argument, our selection dynamic can explain certain "altruistic" and "spiteful" behaviors that are consistent with individuals having social preferences.
Weibull
Jörgen W
JW
Stockholm School of Economics, Box 6501, SE-113 83 Stockholm, Sweden. jorgen.weibull@hhs.se
Salomonsson
Marcus
M
D000818:Animals; D005716:Game Theory; D006126:Group Processes; D006801:Humans; D007398:Interpersonal Relations; D008957:Models, Genetic; D008960:Models, Psychological; D012641:Selection, Genetic