Thurgau Institute of Economics (TWI), University of Konstanz, Hauptstrasse 90, 8280 Kreuzlingen, Switzerland.
J Theor Biol. 2012 Dec 21;315:128-38. doi: 10.1016/j.jtbi.2012.09.012. Epub 2012 Sep 25.
Models of evolutionary game theory have shown that punishment may be an adaptive behaviour in environments characterised by a social-dilemma situation. Experimental evidence closely corresponds to this finding but questions the cooperation-enhancing effect of punishment if players are allowed to retaliate against their punishers. This study provides a theoretical explanation for the existence of retaliating behaviour in the context of repeated social dilemmas and analyses the role punishment can play in the evolution of cooperation under these conditions. We show a punishing strategy can pave the way for a partially cooperative equilibrium of conditional cooperators and defecting types and, under positive mutation rates, foster the cooperation level in this equilibrium by prompting reluctant cooperators to cooperate. However, when rare mutations occur, it cannot sustain cooperation by itself as punishment costs favour the spread of non-punishing cooperators.
进化博弈论模型表明，在具有社会困境的环境中，惩罚可能是一种适应性行为。实验证据与这一发现非常吻合，但如果允许玩家报复惩罚者，那么惩罚对合作的促进作用就会受到质疑。本研究从理论上解释了在重复的社会困境中报复行为的存在，并分析了在这种情况下惩罚在合作进化中的作用。我们表明，惩罚策略可以为有条件的合作者和背叛者的部分合作均衡铺平道路，并在正突变率下，通过促使不情愿的合作者合作，促进这一均衡中的合作水平。然而，当稀有突变发生时，它本身无法维持合作，因为惩罚成本有利于非惩罚合作者的传播。
