Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This article studies experimentally to what extent subjects can cooperate in a dynamic common pool game, where the stage game changes endogenously. Although efficiency can be supported with strategies that condition on history, the main finding is that it is difficult to cooperate. Even if the incentives to cooperate are large, modal behavior can be rationalized with equilibrium Markov strategies that do not condition on history. The popularity of Markov strategies, however, is decreasing in the incentives to cooperate. The evidence also suggests that strategic uncertainty added by facing stage games that change in time may move play away from efficiency.