The Communality of Risk: Differentiating the Logic of Risk Governance Based on Evolutionary Game Theory

Human beings live in a world full of risks, from minor risks such as colds and fevers to major crises such as economic crises and hurricanes. How to cope with these risks is a constant topic in the evolution of humankind. The impact of various characteristics of risk on the risk-resistance outcomes has been well studied, including the probability, intensity and spread of risks. However, as an additional dimension independent of the above main characteristics, risk-resistance solutions that are appropriate to the risk have not received sufficient attention. We abstract this characteristic as the relative cost-effectiveness between collective solution and individual solution in resisting a risk and name it communality. Taking communality and intensity as the two main characteristics of risk, we propose a risk-resistance model and explore the critical impact of risk communality on the outcomes of risk resistance. Using numerical analysis, we map the state transition of the population on a two-dimensional surface consisting of communality and intensity. Simulation experiments validate the results from numerical analysis and reveal four regions in this surface, each of which corresponds to a governance structure endogenous to the population. The complex impact of population-endogenous governance structures on the risk-resistance outcomes reflects the real-world challenges of risk governance. This article suggests that social governors need to implement different logics in the face of risks with different communalities.