title: Cooperation in spatial prisoner's dilemma with two types of players for increasing number of neighbors.
abstract: We study a spatial two-strategy (cooperation and defection) prisoner's dilemma game with two types ( A and B ) of players located on the sites of a square lattice. The evolution of strategy distribution is governed by iterated strategy adoption from a randomly selected neighbor with a probability depending on the payoff difference and also on the type of the neighbor. The strategy adoption probability is reduced by a prefactor (w<1) from the players of type B . We consider the competition between two opposite effects when increasing the number of neighbors ( k=4 , 8, and 24). Within a range of the portion of influential players (type A ) the inhomogeneous activity in strategy transfer yields a relevant increase (dependent on w ) in the density of cooperators. The noise dependence of this phenomenon is also discussed by evaluating phase diagrams.
authors.affiliation: Research Institute for Technical Physics and Materials Science, H-1525 Budapest, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Szabó
authors.forename: Attila
authors.initials: A
authors.lastname: Szolnoki