There is a longstanding concern that material incentives might undermine prosocial motivation, leading to a decrease in blood donations rather than an increase. This paper provides an empirical test of how material incentives affect blood donations in a large-scale field experiment spanning...

A vast body of empirical studies lends support to the incentive effects of rank-order tournaments. Evidence comes from experiments in laboratories and non-experimental studies exploiting sports or firm data. Selection of competitors across tournaments may bias these non-experimental studies,...