We analyse interethnic cooperation in an infinitely repeated prisoner's dilemma when members of one group are unable to target punishment towards individual defectors from the other group. We first show that indiscriminate outgroup punishment may sustain cooperation in this setting. Our main...

Previous research shows that collective action to avoid a catastrophic threshold, such as a climate "tipping point", is unaffected by uncertainty about the impact of crossing the threshold but that collective action collapses if the location of the threshold is uncertain. Theory suggests that...

A novel version of a Voluntary Contribution Mechanism game tests how player cooperation responds to changes in incentives, i.e., payoffs that depend on performance relative to different reference groups. Cooperation is greatest when players are competing against players in other four-person...

Abstract: This essay makes a conceptual distinction between societal categories, such as social networks, norms, and social status differentiation, on the one hand, and social capital, on the other. The former are institutional phenomena arising as outcomes of social-exchange games in which...

We study the evolution of cooperation in spatial public goods games with four competing strategies: cooperators, defectors, punishing cooperators, and punishing defectors. To explore the robustness of the cooperation-promoting effect of costly punishment, besides the usual strategy adoption...

Strategy changes are an essential part of evolutionary games. Here we introduce a simple rule that, depending on the value of a single parameter w, influences the selection of players that are considered as potential sources of the new strategy. For positive w players with high payoffs will be...

Standard game theory turns a blind eye toward social interaction between the players in a game. Hence, a given game offers the same set of equilibria regardless of the identities of the players and the specifics of the social context. The predictive value of game theory is severely limited as a...

In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs) is particularly puzzling. Here we propose a novel approach to...

Mentalising is assumed to be involved in decision-making that is necessary to social interaction. We investigated the relationship between mentalising and two types of strategic games - those involving the choice to cooperate with another for joint gain or compete for own gain and those...