Investing Time in the Public Good: A Web-based Threshold Public Good Experiment

In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment that uses participants time as their natural endowment, which can be invested in the public good experiment. The experiment runs for several days and participants can make contributions to the threshold public good by logging into a web application and performing virtual actions. Like traditional experiments we find an initial high level of contributions that decreases over subsequent days. We compared two treatments, with and without leaderboards, which compared the real-time performance of groups. We find that the leaderboard increases contributions during the first day, but in subsequent days no significant positive effect is found. Groups with low performances on the first day may have given up when confronted with the leaderboard rankings. These findings show the double-edged effect of information feedback.