中文摘要：

群体性突发事件是一类人们未曾预料到的事件，其发生会影响社会系统的正常运行。作为一类特殊的群体行动，它是一定数量行动主体采取某种行动的结果。从选择逻辑的角度看，行动主体是在做出选择后行动的，而其选择是受其偏好影响的，偏好又是行动主体认知世界中认知状态的产物，即信念使然。群体性突发事件的出现有其逻辑上的必然性，对这类事件进行干预进而最终能够消除也是逻辑必然的。日本大地震后，受核泄漏影响在我国出现的抢盐事件以及及时消除说明，信息的获取影响公众偏好的形成，能否获取正确信息，是群体性突发事件发生与否的一个关键因素。

英文摘要：

Group emergency, as a sort of unexpected incident, will inevitably affect the regular operation of social system. And as a kind of special group action, it is the result of a certain number of agents taking action. From point of view of choice logic, agent＇ s action is followed by his choice, while preference affects agent＇ s choice, and preference is a product of his cognitive state in epistemological world, i.e. that is what the belief brings. The occurring of group emergency has logical necessity, and it is logical necessity to eliminate group emergency through intervention. Nuclear leak ＇after severe earthquakes in Japan attracts worldwide attention. China＇ s great salt rush and elimination of it show that information acquisition can influence the public＇ s preference, and that whether relevant information is true is a key factor in the occurring of group emergency.