关键词: 突发公共卫生事件, 预警信息公开, 参照依赖, 演化博弈

Abstract: Over the past few years, there have been various public health emergencies around theworld. Warning disclosure is an important part of infectious disease early prevention. Local governments need to be responsible for reporting the epidemic progress to higher authorities timely, while releasing warning to the public and guiding them to take self-protective measures. If local governments delay, conceal, or abandon warning, it is hard for other participants to access epidemic information. Risk communication channels will be broken and negative information such as rumors, misinformation and disinformation will be generated, thus increasing panicofthe public. However, current researches have concerned little about how local governments make strategic choices on warning releasing, especially in unknown epidemic. Toaddressthegap, atripartite evolutionary game model is constructed. This study will guide policy-makers decision making in public health emergencies and provide model support for their formulation of rights, responsibilities.
In existing studies, decision makers have been often assumed to be completely rational. However, in the emergency situation, this is difficulttoachievedue to uncertainty of epidemic, incomplete information, and participants' cognitive limitations. Decision makers are characterized as bounded rationality. Bounded rationality includes a wide range of behavioral tendencies, one of which is the reference dependence proposed by Kahneman and Tversky in prospect theory.According to reference dependence theory, the outcome of participant in decision making is not determined by absolute utility. Rather, it is replaced by subjective perceived utility based on a reference point. Therefore, based on the assumption of bounded rationality, the traditional expected utility function is changed in the model of this paper. The reference dependent theory is introduced to describe the cognition and decision-making rules of participants in emergency situations. First, atripartite evolutionary game model of local government, central government, and the public is established. Second, an interactive behavior of different stakeholders is described by establishing a copy dynamic equation. The model demonstrates the dynamic behavioral trajectory of three participants. Finally, numerical simulation experiments are conducted to test the system stability conditions and the three-party strategy choice under different parameters.
The results show that an increase in the proportion of either central governments supervision or public participation strategies in the initial state positively affects warning disclosure of local governments. The two have formed a benign complementary embedding. In comparison, local governments respond more quickly to the force of central government, and the system reaches a stable state more quickly. For central government, the best strategy among active and passive supervision can be chosen according to the strategy of public (whistle blowers) participation in public health emergencies. The results also show that local governments' warning decisionis determined by theresult of the interactive game between decision makers with different perceived utility. Both the perceived utility and the cost of information disclosure have obvious driving effects on the system evolution. Thesystem issensitiveto both marginaldiminishing sensitivity degree coefficient and the aversion loss degree coefficient. In addition, appropriately increasing the success rate of central government supervision, improving the level of local government risk judgment, and strengthening the accuracy of public information identification areimportant to promote warning disclosure.
To combat other pandemic effectively, our findings have several practice-relevant implications. First, the central government should improve supervision success rate and develop a reasonable institutions of local government accountability. A fault tolerance mechanism and an exemption clause should be established as a way to encourage local governments to disclosure warning in the public health emergencies. Second, local governments should have clear, objective and realistic understanding of risk information. They should try to avoid mistakes like avoidance of accountability, cognitive bias, and risk aversion in decision-making.They should reduce the value judgment of local government officials on the cost of warning dissemination by unblocking information channels, improving the scope of information delivery, and enhancing the effectiveness of risk communication.The negative economic and social impacts of epidemic outbreak need to be fully understood by local policy-makers in public health emergencies. Third, incentives should be given to promote whistle blowers to participate in early warning of infectious diseases. Appropriate involvement of social forces represented by NGO, enterprises and citizens could help the government to avoid the problems of “information noise” and “information overload”. In order to effectively prevent the overall failure of epidemic warning, the policy-makers need to recognize the legitimacy of community self-organized warning dissemination.
There are still some limitations that can be worked for by further study. First, the parameter setting of numerical simulation relies on interview data, rather than observations of real cases. Additional validation will be done by collecting official data. Second, only the relationship between upper and lower levels of government is considered. The exchange of warning between governments at the same level during public health emergencies also needs to be considered in future studies.

Key words: public health emergencies, warning disclosure, reference dependence, evolutionary game