This paper develops and tests several models of pure Nash strategies of individuals who extract from a common pool resource when they are motivated by a combination of self-interest and preferences for altruism, reciprocity, inequity aversion, or conformity. Using data from experiments conducted in three regions of Colombia that depend critically on a local fishery, we test whether an econometric summary of the subjects' pure Nash strategies is consistent with one or more of these models. We find that a model that balances self-interest with a strong preference for conformity best describes average strategies.
