Beschreibung:
The frequent occurrence of major emergencies causes credit default and its contagion among counterparties in the financial market, which is of great importance to the study of counterparty credit risk contagion control under the impact of major emergencies. In view of this background, this study constructed the SIs-EIeRS model of counterparty credit risk contagion caused by major emergencies on the basis of complex network theory and the infectious disease model. This research also analyzed the mechanism and evolution characteristics of counterparty credit risk contagion through theoretical deduction and computational simulation. On this basis, we combined the Mansfield diffusion model and nonlinear system dynamics theory, constructed the counterparty credit risk contagion control model under the impact of major emergencies, and analyzed the evolution characteristics and optimal control strategy selection of counterparty credit risk contagion control under major emergencies through theoretical deduction and computational simulation. The results showed the following. 1) When the recombination rate of bankrupt credit subjects is small, the default rate of the normal credit subject without the impact of major emergencies and the impact strength of major emergencies is small. Furthermore, the counterparty credit risk contagion scale decreases with the increase of the impact strength of major emergencies. However, in other cases, the counterparty credit risk contagion scale increases with the impact strength of major emergencies. 2) Under the differential influence of major emergencies on the default rate, bankruptcy rate, and recovery rate of the affected credit subjects, the evolution of the counterparty credit risk contagion scale tends to increase or decrease first and then increase with the increase of the impact strength of major emergencies. 3) Under the four types of control strategies, namely, pre-prevention control, blocking control, lagging recovery control, and comprehensive control, the counterparty credit risk contagion scale increases first and then decreases to the stable target value. However, the stable control level of counterparty credit risk contagion is different. 4) Considering the effect of counterparty credit risk contagion control and social resource consumption comprehensively, both lagging recovery control strategy and comprehensive control strategy may be the optimal strategies, and different optimal strategies may be selected with the change of contagion conditions under the impact of major emergencies