In this paper I examine the influence which a population of different behavioral types may have on the provision of public goods. In particular, the population or subject pool consists of three behavioral types: myopic selfish agents, enlightened selfish agents and ethically motivated agents. I...

We develop a model that accounts for the decay of the average contribution observed in experiments on voluntary contributions to a public good. The novel idea is that people's moral motivation is "weak." Their judgment about the right contribution depends on observed contributions by group...