To understand the “pure” incentives of altruism, economic laboratory research on humans almost always forbids communication between subjects. In reality, however, altruism usually requires interaction between givers and receivers, which clearly must influence choices. Charities, for example,...

To understand the "pure" incentives of altruism, economic laboratory research on humans almost always forbids communication between subjects. In reality, however, altruism usually requires interaction between givers and receivers, which clearly must influence choices. Charities, for example,...