Why do money and markets crowd out co-operative relations? This paper characterises the effects of intertemporal preferences, money, and markets on players' ability to co-operate in material-payoff supergames. Players' aversion to intertemporal substitution facilitates co-operation by decreasing...

We examine the characteristics of effective leaders in a simple leader-follower voluntary contributions game. We focus on two factors: the individual's cooperativeness and the individual's beliefs about the cooperativeness of others. We find that groups perform best when led by those who are...

We experimentally examine how the incentive to defect in a social dilemma affects conditional cooperation. In our first study we conduct online experiments in which subjects play eight Sequential Prisoner's Dilemma games with payoffs systematically varied across games. We find that few second...

We study the effect of group size on cooperation in voluntary contribution mechanism games. As in previous experiments, we study four- and eight-person groups in high and low marginal per capita return (MPCR) conditions. We find a positive effect of group size in the low MPCR condition, as in...