We consider payment schemes in experiments that model infinite-horizon games by using random termination. We compare paying subjects cumulatively for all periods of the game; with paying subjects for the last period only; with paying for one of the periods, chosen randomly. Theoretically, assuming expected utility maximization and risk neutrality, both the cumulative and the last period payment schemes induce preferences that are equivalent to maximizing the discounted sum of utilities. The last period payment is also robust under different attitudes toward risk. In comparison, paying subjects for one of the periods chosen randomly creates a present-period bias. We further provide experimental evidence from infinitely repeated prisoners’ dilemma games that supports the above theoretical predictions.

Dynamic externalities are at the core of many long-term environmental problems, from species preservation to climate change mitigation. We use laboratory experiments to compare welfare outcomes and underlying behavior in games with dynamic externalities under two distinct settings: traditionally studied games with infinitely-lived decision makers, and more realistic intergenerational games. We show that if decision makers change across generations, resolving dynamic externalities becomes more challenging for two distinct reasons. First, decision makers’ actions may be short-sighted due to their limited incentives to care about future generations’ welfare. Second, even when the incentives are perfectly aligned across generations, the increased strategic uncertainty of the intergenerational setting may lead to an increased inconsistency of own actions and beliefs about others, making own actions more myopic. Access to history and advice from previous generations may improve dynamic efficiency but may also facilitate coordination on noncooperative action paths.