title: Random allocation of pies promotes the evolution of fairness in the Ultimatum Game.
abstract: In the Ultimatum Game, two players are offered a chance to win a pie. The proposer suggests how to split the pie. The responder can either accept or reject the deal. If an agreement is not reached, neither player gets anything. Both game theory and evolutionary game theory predict the rational solution that the proposer offers the smallest possible share and the responder accepts it. Fairness thus requires additional mechanisms for natural selection to favor it. Studies to date assumed that individuals have competed for the fixed size of pies, in sharp contrast with real situations, where randomness is ubiquitous. Here we study the impact of random allocation of pies on the evolution of fairness in the Ultimatum Game. Interestingly, we find that the evolution of fairness can be promoted by the randomness associated with the size of pies, without the support of any additional evolutionary mechanisms.
authors.affiliation: Center for Complex Systems, Xidian University, Xi'an 710071, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Evolution and Ecology Program, International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361 Laxenburg, Austria.
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Chen
authors.affiliation: Center for Systems and Control, State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, China.
authors.forename: Long
authors.initials: L
authors.lastname: Wang
mesh_terms: D005717:Games, Experimental; D006801:Humans; D008962:Models, Theoretical; D011897:Random Allocation