Cuesta J A, Jiménez R, Lugo H, Sánchez A
Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, Leganés, Spain.
J Theor Biol. 2008 Mar 21;251(2):253-63. doi: 10.1016/j.jtbi.2007.11.022. Epub 2007 Nov 22.
One of the most direct human mechanisms of promoting cooperation is rewarding it. We study the effect of sharing a reward among cooperators in the most stringent form of social dilemma, namely the prisoner's dilemma (PD). Specifically, for a group of players that collect payoffs by playing a pairwise PD game with their partners, we consider an external entity that distributes a fixed reward equally among all cooperators. Thus, individuals confront a new dilemma: on the one hand, they may be inclined to choose the shared reward despite the possibility of being exploited by defectors; on the other hand, if too many players do that, cooperators will obtain a poor reward and defectors will outperform them. By appropriately tuning the amount to be shared a vast variety of scenarios arises, including the traditional ones in the study of cooperation as well as more complex situations where unexpected behavior can occur. We provide a complete classification of the equilibria of the n-player game as well as of its evolutionary dynamics.
促进合作最直接的人类机制之一就是给予奖励。我们在社会困境最严格的形式，即囚徒困境（PD）中，研究在合作者之间分享奖励的效果。具体而言，对于一组通过与伙伴进行两两囚徒困境博弈来获取收益的玩家，我们考虑一个外部实体，它将固定奖励平均分配给所有合作者。因此，个体面临一个新的困境：一方面，尽管可能被背叛者利用，他们可能仍倾向于选择共享奖励；另一方面，如果太多玩家这样做，合作者将获得较差的奖励，而背叛者的表现将优于他们。通过适当地调整共享的数量，会出现各种各样的情况，包括合作研究中的传统情况以及可能出现意外行为的更复杂情况。我们提供了n人博弈均衡及其进化动力学的完整分类。
