Understanding the proximate and ultimate sources of human cooperation is a fundamental issue in all behavioural sciences. In this article we review the experimental evidence on how people solve cooperation problems. Existing studies show without doubt that direct and indirect reciprocity are...

We investigate whether there is a link between conditional cooperation and betrayal aversion. We use a public goods game to classify subjects by type of contribution preference and by belief about the contributions of others; and we measure betrayal aversion for different categories of subject....

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...

This chapter presents some insights from basic behavioural research on the role of human pro-social motivation to maintain social order. I argue that social order can be conceptualised as a public good game. Past attempts to explain social order typically relied on the assumption of selfish and...

We study the effects of voluntary participation on cooperation in collective action problems. Voluntary participation may foster cooperation through an entry mechanism, which leads to assortative selection of interaction partners, or an exit mechanism, whereby the opportunity to leave the...

We study information conditions under which individuals are willing to delegate their sanctioning power to a central authority. We design a public goods game in which players can move between institutional environments, and we vary the observability of others' contributions. We find that the...

We experimentally investigate how different information about others' individual contributions affects conditional cooperators' willingness to cooperate in a one-shot linear public goods game. We find that when information about individual contributions is provided, contributions are generally...

We study the effects of voluntary participation on public good provision. Voluntary participation may foster cooperation through two mechanisms: an entry mechanism, which leads to assortative selection of interaction partners, or an exit mechanism, whereby the opportunity to leave the...

While numerous experiments demonstrate how pro-sociality can influence economic decision-making, evidence on explicitly anti-social economic behavior has thus far been limited. In this paper we investigate the importance of spite in experimental rent-seeking contests. Although, as we show,...

One lingering puzzle is why voluntary contributions to public goods decline over time in experimental and real-world settings. We show that the decline of cooperation is driven by individual preferences for imperfect conditional cooperation. Many people's desire to contribute less than others,...