The effects of dynamic peer pressure on the evolution of cooperation in complex networks

In collective life, individuals find it difficult to avoid being influenced by their environment. In the spatial evolutionary game, the surrounding peers constitute the local environment of individuals. The difference in strategy from peers can make individuals feel pressure, which affects the evolution of cooperation by altering individuals’ behavioural decision-making. However, previous studies on the effects of peer pressure on cooperation have primarily focused on oversimplified network structures and assumed constant pressure sensitivity among all players, which has limited our understanding of the impact of peer pressure on the evolution of cooperation in more complex environments. This paper presents an evolutionary game model in which individual’s sensitivity to pressure is different from each other and dynamically adjusted with the change of strategies among the surroundings, capturing a more realistic portrayal of social influence and psychological factors. We examine how the dynamic sensitivities and the intensity of peer pressure affect the evolutionary dynamics by conducting the simulations on both Watts-Strogatz (WS) network and Barabási-Albert (BA) network. Our findings reveal that peer pressure with dynamic sensitivity exhibits completely different effects on cooperation for the WS and BA network, that is, it can greatly enhance cooperation on the WS network while inhibiting cooperation on the BA network. Besides, a lower level of pressure intensity can be more conductive to the evolution of cooperation, whether in WS network or BA network.