A large and growing literature links high levels of ethnic diversity to low levels of public goods provision. Yet while the empirical connection between ethnic heterogeneity and the underprovision of public goods is widely accepted, there is little consensus on the specific mechanisms through...

We study the long-term determinants of the high rates of HIV infection in sub-Saharan Africa, particularly among women, with a focus on family structure and sexual behavior as shaped by the demographic shock following the transatlantic slave trade. First we show that, in clusters where polygyny...

We test if cooperation is promoted by rank-order competition between groups in which all groups can be ranked first, i.e. when everyone can be a winner. This type of rank-order competition has the advantage that it can eliminate the negative externality a group's performance imposes on other...

When multiple charities, social programs and community projects simultaneously vie for funding, donors risk miscoordinating their contributions leading to an inefficient distribution of funding across projects. Community chests and other intermediary organizations facilitate coordination among...

Using a negatively framed public good game, we study the cooperative behavior of individuals who reintegrate their group after being excluded by their peers. We manipulate the length of exclusion and whether this length is imposed exogenously or results from a vote. We show that people are...

Sanctions are a common method to discourage free-riding in the provision of public goods. However, we can usually only sanction those who are detected performing the bad act of free-riding. There has been considerable research on the type of sanctions imposed, but this research almost always...

The ability to punish free-riders can increase the provision of public goods. However, sometimes the benefit of increased public good provision is outweighed by the costs of punishments. One reason a group may punish to the point that net welfare is reduced is that punishment can express anger...

We investigate the link between leadership, beliefs and pro-social behavior. This link is interesting because field evidence suggests that people's behavior in domains like charitable giving, tax evasion, corporate culture and corruption is influenced by leaders (CEOs, politicians) and beliefs...

We study the dynamics of the private provision of a public good that requires both capacity buildup and ongoing operating costs. We show that setting a time limit for the collection of contributions dedicated to capacity buildup minimizes the utility loss at the Nash equilibrium. We test the...

In a novel experimental design we study public good games with dynamic interdependencies. Each agent's income at the end of a period serves as her endowment in the following period. In this setting growth and inequality arise endogenously allowing us to address new questions regarding their...