Much fundraising is done by individuals within existing social groups. Exploiting a unique dataset, we demonstrate (i) a positive relationship between social group size and the number of donations; (ii) a negative relationship between group size and the size of individual donations; (iii) no...

We study charitable giving within social groups. Exploiting a unique dataset, we establish three key relationships between social group size and fundraising outcomes: (i) a positive relationship between group size and the total number of donations; (ii) a negative relationship between group size...