In this paper, we use the classical twin design to provide estimates of genetic and environmental influences on experimentally elicited preferences for risk and giving. Using standard methods from behavior genetics, we find strong prima facie evidence that these preferences are broadly heritable...

We analyze the effects of family ties - quot;the fetters of the sibquot; - on the incentives for productive effort. A family is here modeled as a pair of mutually altruistic siblings. Each sibling exerts effort, or makes an investment, to produce output under uncertainty, and siblings may...