Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Through a series of experiments, this paper tests the relative efficiency of persuasion and commitment schemes to increase and sustain contribution levels in a Voluntary Contribution Game. The design allows us to compare a baseline consisting of a repeated public good game to four treatments of the same game in which we successively introduce a persuasion message, commitment devices, and communication between subjects. Our results suggest that these non-monetary procedures significantly increase cooperation and reduce the decay of contributions across periods.