Reciprocity can be a powerful motivation for human behaviour. Scholars argue that it is relevant in the context of private provision of public goods. We examine whether reciprocity can resolve the associated coordination problem. The interaction of reciprocity with cost-sharing is critical....

Individuals often have legitimate but publicly unobservable reasons for not partaking in cooperative social endeavours. This means others who lack legitimate reasons may then have the opportunity to behave uncooperatively, i.e. free-ride, and be indistinguishable from those with legitimate...

Many fundraisers report donations using categories such as more than £ 1000, more than £ 10,000 etc. One naturally wonders how we should categorise donations and whether category reporting can raise more funds than simple uncategorised reporting. To shed light on these questions, we employ a...

In a signalling model of conformity, we demonstrate that naïve observers, those that take actions at face value, constrain the set of actions that can possibly be social norms. With rational observers many actions can be norms, but with naïve observers only actions close to that preferred by...

We develop, and experimentally test, models of informal agreements. Agents are assumed to be honest but suffer costs of overcoming temptations. We extend two classical bargaining solutions -- split-the-difference and deal-me-out -- to this informal agreement setting. For each solution there are...

We develop, and experimentally test, a behavioral model of deal- making which includes binding contracts and informal agreements as distinct but related special cases. The key assumptions: people are mostly honest; they suffer costs of overcoming temptation to renege; and they tend to split gains...