Reciprocity: Weak or Strong? What Punishment Experiments Do (and Do Not) Demonstrate

Abstract

Strong Reciprocity theorists claim that cooperation in social dilemma games can be sustained by costly punishment mechanisms that eliminate incentives to free ride, even in one-shot and finitely repeated games. There is little doubt that costly punishment raises cooperation in laboratory conditions. Its efficacy in the field however is controversial. I distinguish two interpretations of experimental results, and show that the wide interpretation endorsed by Strong Reciprocity theorists is unsupported by ethnographic evidence on decentralised punishment and by historical evidence on common pool institutions. The institutions that spontaneously evolve to solve dilemmas of cooperation typically exploit low-cost mechanisms, turning finite games into indefinitely repeated ones and eliminating the cost of sanctioning.JEL Classification: D02, D03, C92, H41, Z1

Sustaining cooperation in laboratory public goods experiments: a selective survey of the literature

“…Furthermore, Guala (2010) points out that ethnographic evidence from tribal societies or the historical evidence on common pool resource usage does not provide a lot of support for either the use or the efficacy of such costly monetary punishments. Therefore, mechanisms that rely less on monetary punishments and more on other factors might be easier to adopt.…”

Cooperation in and out of the lab: a comment on Binmore’s paper

“…Luckily there is a relatively rich body of field evidence on ''naturally evolved'' institutions that sustain cooperation in the wild, coming mostly from anthropology and economic history. Since I have reviewed it at length elsewhere (Guala 2010), and to keep within the limits of this short commentary, in the next section I will briefly discuss one example of common pool institution that emerged spontaneously in the late Middle Ages, taken from the history of my native country. 5…”

“…This is an external validity issue which cannot be resolved by appeal to laboratory data only (cf. Guala 2005Guala , 2010.…”

What can economics contribute to the study of human evolution?

“…All of this is outright formal confusion. The next problem, with the claims that field and ethnographic evidence confirm strong reciprocity, is most decisively exposed by Guala (2010). In a careful review of the anthropological literature, he finds that outside of the lab people enforce their social contracts with spontaneous low-cost punishments like gossiping, ostracism and moving away from offenders, or rely on third-party punishment institutions.…”

“…Confusingly, they like to say that they also observe it in field experiments(Henrich et al 2004); but an overt manipulation of subjects' incentives is not turned into a true field experiment merely by conducting it outdoors in an exotic country(Harrison and List 2004;Guala 2010).…”