Human cooperation in the simultaneous and the alternating Prisoner's Dilemma: Pavlov versus Generous Tit-for-Tat.

The iterated Prisoner's Dilemma has become the paradigm for the evolution of cooperation among egoists. Since Axelrod's classic computer tournaments and Nowak and Sigmund's extensive simulations of evolution, we know that natural selection can favor cooperative strategies in the Prisoner's Dilemma. According to recent developments of theory the last champion strategy of "win--stay, lose--shift" ("Pavlov") is the winner only if the players act simultaneously. In the more natural situation of players alternating the roles of donor and recipient a strategy of "Generous Tit-for-Tat" wins computer simulations of short-term memory strategies. We show here by experiments with humans that cooperation dominated in both the simultaneous and the alternating Prisoner's Dilemma. Subjects were consistent in their strategies: 30% adopted a Generous Tit-for-Tat-like strategy, whereas 70% used a Pavlovian strategy in both the alternating and the simultaneous game. As predicted for unconditional strategies, Pavlovian players appeared to be more successful in the simultaneous game whereas Generous Tit-for-Tat-like players achieved higher payoffs in the alternating game. However, the Pavlovian players were smarter than predicted: they suffered less from defectors and exploited cooperators more readily. Humans appear to cooperate either with a Generous Tit-for-Tat-like strategy or with a strategy that appreciates Pavlov's advantages but minimizes its handicaps.

Att bekämpa det onda eller främja det goda : Fyra verksamhetsperspektiv på individer i våldsbejakandemiljöer samt preventionsarbete runt dessa

To fight evil or promote good: Four organizational perspectives on individuals inviolent environments and prevention work around them. The purpose of this article is to examine organizational understandings and perceptions that can affect the current work with defectors from and members in violent and extremist environments. The empirical material consists primarily of answers to open questions in a survey, where professionals from four organizations are represented: social services, school, police and politics. The material is analyzed with direct qualitative content analysis and shows two contradict approaches to the problem; one that argues for ”fighting the evil” and another that argues for ”promoting the good”. The theoretical framework presented is Erving Goffmans’ frame analysis, Howard S. Beckers’ labelling process and Ingrid Sahlins’ discussion about different kinds of prevention strategies. The results show how organizational understandings and perceptions are far from uniform but rather disparate, and also that assumptions made by professionals have wide implications – often related to morally based approaches grounded on notions of good and evil.