The emergence of reciprocally beneficial cooperation

Sergio Beraldo, Robert Sugden

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1 Citation (Scopus)
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We offer a new and robust model of the emergence and persistence of cooperation when interactions are anonymous, the population is well-mixed, and evolution selects strategies according to material payoffs. The model has a Prisoner’s Dilemma structure, but with an outside option of non-participation. The payoff to mutual cooperation is stochastic; with positive probability, it exceeds that from cheating against a cooperator. Under mild conditions, mutually beneficial cooperation occurs in equilibrium. This is possible because the non-participation option holds down the equilibrium frequency of cheating. Dynamic properties of the model are investigated theoretically and through simulations based on replicator dynamics.
Original languageEnglish
Pages (from-to)501–521
Number of pages21
JournalTheory and Decision
Issue number4
Early online date18 Aug 2015
Publication statusPublished - Apr 2016


  • cooperation
  • voluntary participation
  • random payoffs

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