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arXiv · 1103.3257

The Joker effect: cooperation driven by destructive agents

Alex Arenas·Juan Camacho·José A. Cuesta·Rubén Requejo
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Abstract

Understanding the emergence of cooperation is a central issue in evolutionary game theory. The hardest setup for the attainment of cooperation in a population of individuals is the Public Goods game in which cooperative agents generate a common good at their own expenses, while defectors "free-ride" this good. Eventually this causes the exhaustion of the good, a situation which is bad for everybody. Previous results have shown that introducing reputation, allowing for volunteer participation, punishing defectors, rewarding cooperators or structuring agents, can enhance cooperation. Here we present a model which shows how the introduction of rare, malicious agents -that we term jokers- performing just destructive actions on the other agents induce bursts of cooperation. The appearance of jokers promotes a rock-paper-scissors dynamics, where jokers outbeat defectors and cooperators outperform jokers, which are subsequently invaded by defectors. Thus, paradoxically, the existence of destructive agents acting indiscriminately promotes cooperation.

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Alex Arenas, Juan Camacho, José A. Cuesta, Rubén Requejo. 2011-03-16. The Joker effect: cooperation driven by destructive agents. https://doi.org/10.1016/j.jtbi.2011.03.017

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