title: Effects of encounter in a population of spatial prisoner's dilemma players.
abstract: We study the evolution of cooperation in spatial prisoner's dilemma games, whereby each player extends its interaction scope by trying to interact with a certain number of encounters randomly chosen from its non-neighbors, in addition to its permanently linked nearest neighbors. Furthermore, the non-neighbors treat the initiative interactions in two scenarios: definitely accepting that from the cooperators, whereas guardedly interacting with defectors with an acceptance probability which may take arbitrary value in [0,1]. Importantly, our results reveal that the proposed encounter mechanism is a potent extrinsic factor that is able to boost cooperation when appropriately adjusting the values of the encounter number and acceptance probability, though rational players would always defect in one-shot encounters, regardless of the action from the counterparts. We hope our studies may help understand that the proposed encounter mechanism is also an important ingredient of a flourishing cooperative society.
authors.affiliation: State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, China. zhcy@pku.edu
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zhang
authors.forename: Jianlei
authors.initials: J
authors.lastname: Zhang
authors.forename: Guangming
authors.initials: G
authors.lastname: Xie
authors.forename: Long
authors.initials: L
authors.lastname: Wang
mesh_terms: D005716:Game Theory; D006801:Humans; D008962:Models, Theoretical; D011336:Probability