No Substitute for the Real Thing: The Importance of In-Context Field Experiments In Fundraising.

We present a complete empirical case study of fundraising campaign decisions that demonstratesthe importance of in-context field experiments. We first design novel matching-basedfundraising appeals. We derive theory-based predictions from the standard impure altruismmodel and solicit expert opinion about the potential performance of our interventions. Boththeory-based prediction and descriptive advice suggest improved fundraising performance from aframing intervention that credited donors for the matched funds (compared to a typical matchframing). However, results from a natural field experiment with prior donors of a non-profitshowed significantly poorer performance of this framing compared to a regularly framedmatching intervention. This surprising finding was confirmed in a second natural fieldexperiment, to establish the ground truth. Theoretically, our results highlight the limitations ofboth impure altruism models and of expert opinion in predicting complex “warm glow”motivation. More practically, our results question the availability of useful guidance, andsuggest the indispensability of field testing for interventions in fundraising.