Why give if others will? Evidence of crowd-out in a crowdfunding platform

The increasing use of dynamic fundraising schemes such as crowdfunding has given rise to a relatively small but growing body of literature focusing on understanding the effectiveness of such techniques. In this paper, we first present a simple model of dynamic fundraising as a sequential-move threshold public goods game. We demonstrate that donors have an incentive to free-ride on expected future contributions, which leads to the following testable hypotheses for our empirical analysis: Donations are, all else equal, decreasing in accumulated past donations and increasing in time from the beginning of fundraising. In the next step, we analyse a rich dataset from a prominent crowdfunding platform. We find evidence that supports our hypotheses and shows the presence of a small but statistically significant forward-looking crowd-out among donors. On average, a one-percentage-point increase in past cumulative donations leads to a reduction of 0.05 percentage points in the amount contributed, while a one-percentage-point increase in time passed results in an increase of 0.03 percentage points in the amount contributed. In short, we observe that an increased prospect of future provision crowds out earlier contributions.