There is a general presumption that social preferences can be ignored if markets are competitive. Market experiments (Smith 1962) and recent theoretical results (Dufwenberg et al. 2008) suggest that competition forces people to behave as if they were purely self-interested. We qualify this view....

There is a general presumption that social preferences can be ignored if markets are competitive. Market experiments (Smith 1962) and recent theoretical results (Dufwenberg et al. 2008) suggest that competition forces people to behave as if they were purely self-interested. We qualify this view....

Most economic models are based on the self-interest hypthesis that assumes that all people are exclusively motivated by their material self-interest. In recent years experimental economists have gathered overwhelming evidence that systematically refutes the self-interest hypothesis and suggests...