不确定环境下国际反恐联盟随机演化博弈模型

Stochastic evolutionary game model of international anti-terrorism alliance under uncertain environment

国际反恐联盟成员国反恐决策面临着大国政治角逐、宗教信仰与民族结构等外部复杂的随机性因素影响,为国际反恐局势带来了高度的不确定性.本文针对高度不确定环境下国际反恐态势,构建了基于Moran过程的随机演化模型,分别计算出随机因素主导、期望收益主导和超期望收益主导三种情境下,反恐联盟成员国政府反恐策略在不同随机干扰强度下的均衡结果.研究表明,反恐联盟成员国政府采取"先发制人"或"被动反应"的反恐决策,主要取决于三个因素:1)外部随机性因素;2)反恐联盟的规模;3)不同反恐策略的成本收益.如果随机因素造成非理性决策占据主导地位,则两种策略的成本收益和成员国数量决定了成员国策略选择.如果期望收益占据决策主导地位,只有当反恐联盟的成员国数量大于一定的临界规模时,"先发制人"反恐策略才会成为所有成员国的普遍共识.否则,"被动反应"的反恐搭便车行为将成为稳定状态.

The counter-terrorism decision-making of the members of the international anti-terrorism coalition is faced with externally complicated random factors such as political competition,religious beliefs and national structure,which brings about high uncertainty for the international counter-terrorism situation.This paper constructs a stochastic evolution model based on the Moran process for the international anti-terrorism situation in a highly uncertain environment.Then,the equilibrium results of the counterterrorism strategies under different random disturbance intensities are calculated under the three scenarios of stochastic factor dominance,expected payoff dominance and super-expected payoff dominance.Studies have shown that the governments adopt"preemptive strike"or"passive response"strategy,which mainly depend on three factors:1)Irrational external random factors;2)The scale of the anti-terrorist coalition;3)Cost-benefit of different counter-terrorism strategies.If the irrational random factors dominate the decision-making,the cost-benefit of the two strategies and the numbers determine the strategic choice of the member states.If the expected payoff dominates the decision-making,the"preemptive strike"strategy will become the general consensus of all member states only when the number of members of the anti-terrorist coalition is greater than a numerical value.Otherwise,the"passive response"anti-terrorist free-riding behavior will become stable strategy.