An experimental study of time-independent and time-dependent externalities in the commons

The use of common-pool resources (CPRs) implies the existence of appropriation externalities. Benchmark predictions are derived and experiments conducted for a CPR game in which the appropriation externality is either time-independent or time-dependent. In the time-independent setting, externalities are restricted to within a decision period. In the time-dependent setting, externalities occur both within and across decision periods. Subject behavior is generally found to be consistent with noncooperative solution benchmarks. Further, efficiency tends to be lower in time-dependency settings, often with behavior that is best characterized as temporally myopic. (C) 1997 Academic Press.