When is punishment harmful to cooperation? A note on antisocial and perverse punishment

Economists conducting laboratory experiments on cooperation and peer punishment find that a non-negligible minority of punishments is directed at cooperators rather than free riders. Such punishments have been categorized as 'perverse' or 'antisocial,' using definitions that partially overlap, but not entirely so. Which approach better identifies punishment that discourages cooperation? We analyze the data from 16 sites studied by Herrmann et al. (Science 319(5868):1362-1367, 2008) and find that when subjects are uninformed about who punished them, the recipient's contribution relative to the group average (whether it is 'perverse') is a better predictor of negative impact on contribution than is her contribution relative to the punisher's (whether it is 'antisocial'). Regression estimates nevertheless suggest that punished subjects attempt to take relative contribution of punisher into account even if only by conjecture.