Zhang Chunyan, Zhang Jianlei, Xie Guangming, Wang Long
State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, China.
Theor Popul Biol. 2011 Nov;80(3):226-31. doi: 10.1016/j.tpb.2011.06.007. Epub 2011 Jul 8.
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.
