Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Kocher et al. (2008) find that conditional willingness to contribute to a public good is considerably stronger at a U.S. research site, Appalachian State University, than at sites in Europe and Asia. I find that the willingness at Brown University, in Rhode Island, is not significantly different from that in Europe and Asia in Kocher et al. (2008). Clear evidence on significantly different demographic statistics between these two U.S. research sites is provided. This implies that in the experimental study of societies, or more generally in empirical studies, we need exercise care to generalize from results at a specific research site to geographically broader conclusions.