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...

Spillovers of prosocial motivation are crucial for the formation of social capital. They facilitate interactions among individuals and create social multipliers that amplify the effects of policy interventions. We conducted a large-scale intervention study among dyads of blood donors to...

We report the results of a field experiment with bicycle messengers in Switzerland and the United States. Messenger work is individualized enough that firms can choose to condition pay on it, but significant externalities in messenger behavior nonetheless give their on-the-job interactions the...

Due to incomplete contracts, efficiency of an organization depends on willingness of individuals to take non-selfish actions, e.g., cooperate when there is no incentive to do so, or punish inefficient actions by others. Organizations also constitute a social boundary, or group. We investigate...

How do the complex institutions involved in wage setting affect wage changes? The International Wage Flexibility Project provides new microeconomic evidence on how wages change for continuing workers. We analyze individuals' earnings in 31 different data sets from sixteen countries, from which...

Does social recognition motivate prosocial individuals? We run large-scale experiments among members of Italy's main blood donors association, testing social recognition both through social media and peer groups. We experimentally disentangle visibility concerns and peer comparisons, and we...