We demonstrate how altruism can surge in a population of nonaltruists. We assume that each individual plays a one-shot prisoner's dilemma game with his or her sibling, or with a stranger, and that the probability that an individual survives to reproduce is proportional to his or her payoff in...

The intersection of the standard altruism hypothesis with the quite strong evidence that bequests tend to be equal suggests that inter-vivos transfers should be strongly compensatory. Yet the available evidence is not in congruence with this implication. It has therefore been inferred that the...

This paper investigates four topics. (1) It examines the different roles played by the propensity score (probabilitiy of selection) in matching, instrumental variable and control functions methods. (2) It contrasts the roles of exclusion restrictions in matching and selection models. (3) It...

This paper summarizes our recent research on evaluating the distributional consequences of social programs. This research advances the economic policy evaluation literature beyond estimating assorted mean impacts to estimate distributions of outcomes generated by different policies and determine...

This paper considers the problem of making inferences about the effects of a program on multiple outcomes when the assignment of treatment status is imperfectly randomized. By imperfect randomization we mean that treatment status is reassigned after an initial randomization on the basis of...

This chapter presents an economic approach to character and personality traits with an application to the study of virtue. Economists interpret psychological traits, including character traits and virtue, as strategies that shape responses to situations (actions) determined by underlying...