Attraction and Cooperation in Noisy Environments: Individuals and Groups

This paper presents an attraction mechanism and its impact on cooperation in a society of agents. We adopt the benchmark setting of the Iterated Prisoner’s Dilemma (IPD, [1]) and we implement attraction as a mechanism that changes the usual agent’s behavior (strategy). More specifically, an agent follows its regular strategy unless it faces an attractive agent. In the latter case, she becomes unconditionally cooperative. This mechanism is shown to yield higher average agent scores in tournaments within uniform or mixed populations than if it were not present. Benefits are higher for higher attraction factors, bigger populations or populations of “irrational” agents. We have also studied the impact of the attraction pairing type and we have found that random not necessarily reciprocal pairing is the best, because even in the absence of reciprocity a rational agent can cooperate consistently with a cooperating attracted, even if irrational, opponent. We have experimented with extreme types of agents as well, namely, a “Don Juan” agent that is attracted by all others, and a “Sex Symbol” to whom all others are attracted. Very often, the introduction of a single extreme agent in a society with no other attraction relations may lead to the same result as a regular society with attraction (but without the extreme agent). Finally, we have experimented with groups of interacting agents to identify possible social conditions that enhance cooperation. All our results suggest that psychological mechanisms external to the economic setting can interfere with it and can actually lead to enhanced cooperation and social stability, despite apparent inconsistencies or irrationalities in individual agents behavior. Accordingly, we can sometimes manage some economic systems by manipulating an external social condition that interferes with normal economic behavior.