Importance of tie strengths in the prisonerʼs dilemma game on social networks

Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisonerʼs dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisonerʼs dilemma games.

► Tie strength is used to measure heterogeneous influences of different pairs of nodes.
► Weak ties play a role in maintaining cooperation in prisonerʼs dilemma games.
► Micro-dynamics of nodes are illustrated to explain the conclusion.