We estimate the effect of an increase in time cost on the return behavior of blood donors. Using data from the Australia Red Cross Blood Service, we ask what happens when pro-social behavior becomes more costly. Exploiting a natural variation in which donor wait times are random, we use the...

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...

This paper studies the effects of reminders, and frames used to invoke higher levels of empathy and altruistic motives on the willingness to donate blood. We have conducted a randomized field experiment with 3236 blood donors from Bosnia and Herzegovina, in order to test how effective frames...