While inequality in resource endowments has been shown to affect cooperation levels in groups, much of this evidence comes from studies of within-group inequality. In an online public goods experiment, we instead examine the effects of payoff-irrelevant inequality in resources between groups on...

Using a dictator game experiment, we examine whether the introduction of group identities affects giving. Group identities can activate feelings of in-group love and out-group hate to create an in-group bias. In addition, group identities may spawn social sanctions that are designed to reinforce...

Abundant evidence suggests that high levels of contributions to public goods can be sustained through self-governed monitoring and sanctions. This experimental study investigates the effectiveness of decentralized sanctioning institutions where punishment opportunities are restricted to agents...

We investigate experimentally whether the extent of conditional cooperation in public good games depends on the marginal return to the public good and type of game. The marginal return is varied from 0.2 to 0.4 to 0.8. The 'standard' game, in which three players contribute before a follower, is...

We investigate experimentally whether the extent of conditional cooperation in public good games depends on the marginal per capita return (MPCR) to the public good and type of game. The MPCR is varied from 0.2 to 0.4 to 0.8. The "standard" game, in which three players contribute before a...

We illustrate one way in which a population of boundedly rational individuals can learn to play an approximate Nash equilibrium. Players are assumed to make strategy choices using a combination of imitation and innovation. We begin by looking at an imitation dynamic and provide conditions under...

In has been frequently observed, in both economics and psychology, that individuals tend to conform to the choices of other individuals with whom thy identify. Can such conformity be consistent with self-interested behaviour? To address this question we use the framework of games with incomplete...

In the literature of psychology and economics it is frequently observed that individuals tend to imitate similar individuals. A fundamental question is whether the outcome of such imitation can be consistent with self-interested behaviour. We propose that this consistency requires the existence...

Motivated by issues of imitation, learning and evolution, we introduce a framework of non-co-operative games, allowing both countable sets of pure actions and player types and player types and demonstrate that for all games with sufficiently many players, every mixed strategy Nash equilibrium...

Interpret a set of players all playing the same pure strategy and all with similar attributes as a society. Is it consistent with self interested behaviour for a population to organise itself into a relatively small number of societies? In a companion paper we characterised how large e must be,...