Transplants of donated stem cells save the lives of many patients with blood diseases. Donation is somewhat painful, but rarely has lasting adverse effects. Patients can accept transplants only from donors with compatible immune systems. Those lacking a sibling match must seek donations from the...

This paper surveys the literature on group selection. I describe the early contributions and the group selection controversy. I also describe the main approaches to group selection in the recent literature; fixation, assortative group formation, and reproductive externalities. -- Altruism ; spite...

Intergenerational altruism and contemporaneous cooperation are both important to the provision of long-lived public goods. Equilibrium climate protection may depend more sensitively on either of these considerations, depending on the type of policy rule one examines. This conclusion is based on...

We analyze the role of "the" utility discount rate and its implications to generation-specific and societal altruism and egoism, respectively, in a neoclassical framework. It is worked out clearly, that two different utility discount rates have to be distinguished: An (inverse)...

The future effects of climate change may induce increased intergenerational altruism. But will increased intergenerational altruism reduce the threat of climate change? In this chapter we investigate this question. In a second-best setting with insufficient control of greenhouse gas emissions in...

Recognizing that individualism, or weak family ties, may be favorable to economic development, we ask how family ties interact with climate to determine individual behavior and whether there is reason to believe that the strength of family ties evolves differently in different climates. For this...

This paper considers one altruistic developed country and several heterogeneous developing countries. We demonstrate that the lack of coordination between countries in tackling climate change finds an optimal solution if developing countries can expect to receive development aid transfers from...

We examine how economic incentives affect pro-social behavior through the analysis of a unique dataset with information on more than 14,000 American Red Cross blood drives. Our findings are consistent with blood donors responding to incentives in a standard way; offering donors economic...

A substantial body of research suggests that economists are less generous than other professionals and that economics students are less generous than other students. We address this question using administrative data on donations to social programs by students at the University of Washington....