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arXiv · 2202.02787

Stable cooperation emerges in stochastic multiplicative growth

Lorenzo Fant·Onofrio Mazzarisi·Emanuele Panizon·Jacopo Grilli
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Abstract

Understanding the evolutionary stability of cooperation is a central problem in biology, sociology, and economics. There exist only a few known mechanisms that guarantee the existence of cooperation and its robustness to cheating. Here, we introduce a mechanism for the emergence of cooperation in the presence of fluctuations. We consider agents whose wealth changes stochastically in a multiplicative fashion. Each agent can share part of her wealth as a public good, which is equally distributed among all the agents. We show that, when agents operate with long-time horizons, cooperation produces an advantage at the individual level, as it effectively screens agents from the deleterious effect of environmental fluctuations.

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Lorenzo Fant, Onofrio Mazzarisi, Emanuele Panizon, Jacopo Grilli. 2022-02-06. Stable cooperation emerges in stochastic multiplicative growth. https://doi.org/10.1103/physreve.108.l012401

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