preferences. We obtain a uniquely comprehensive characterization of donation motives using an experiment that varies treatments … using targeted give-aways to certain donors. A simpler fundraising strategy using only the social dimension of donor …

the effects by income source can be explained by social norms. Our first experiment induces random variation in both … earned income and windfall bonuses and shows that only bonuses increases charitable donations. The second experiment uses an … elicited in the second experiment match the donation patterns in the first experiment both overall and across subject …