The impact of neutral reward on cooperation in public good game

The free-rider behavior is widespread in the system, which will not only lead to social dilemma, and even make the entire system collapse. In order to overcome this complex problem, scientists have done a strenuous endeavor. The public goods game is significant for the study of cooperative behavior among complex interactive social system. And much attention has been paid to the proposal of reward and punishment system. Although people always want to reward cooperative behavior in many cases, antisocial behavior is also common in complex human and biological communities, and free-riders may be rewarded, especially without their information. Therefore, we study the public good game with neutral reward in order to explore the evolution of cooperation. In our public good game, individuals with a few strategies reward other individuals with most strategies in a same group, and the dominant players will receive a fixed bonus provide by other vulnerable players. We show that increasing the bonus will directly promote cooperation and resolve the social dilemma.