Give More Tomorrow: Two Field Experiments on Altruism and Intertemporal Choice.

Breman (2011)
Summary by 
Mark Egan

This paper conducted two field experiments to test inter-temporal choices in charitable giving by varying the timing of commitment and payment. Monthly donors were asked to increase their contributions (1) immediately, (2) in one month, (3) in two months.The results are consistent between the two field experiments. Firstly, mean increases in donations are significantly higher when donors are asked to commit to future donations. Secondly, follow-up data shows that the treatment effect is persistent, making the strategy highly profitable to the charity. Finally, there is evidence of heterogeneity in the response to different timelags, indicating differences in inter-temporal choices among donors.