Risk and interaction aversion: screening mechanisms in the Prisoner's Dilemma game

摘要: When the interactions between cooperators (C) and defectors (D) can be partially avoided within a population, there may an overall enhancement of cooperation. One example such screening mechanism occurs in presence risk-averse agents (loners, L) that are neutral towards others, i.e., both L its opponent, whatever strategy, receive same payoff. Their Prisoner's Dilemma (PD) game sustains coexistence far beyond level attained their absence. Another is heterogeneous landscape obtained, for example, by site diluting lattice. In this case, cooperation enhanced with some fraction inactive, interaction-averse sites. By considering interplay mechanisms, we show explosive increase range densities, just above percolation threshold, where neutrality prevented loners become extinct, behavior reverting to pure PD game. Interestingly, despite being usually abundant region. This has compared corresponding loner-free region undiluted case that, besides very small, dominatedby cooperators.