中文摘要：

群体行为的涌现早已是许多社会学家感兴趣的问题,个体的决策受到他们的观察、观念或者是他人决策的期望所影响,我们称之为决策的外部性。通过对选择问题的外向性的规律进行研究建立了效用模型选择模型,再应用复杂网络及多代理主体进行人工模拟来对群体应急行为的动力学进行探索。实验研究结果表明危机中对于决策敏感系数低的选择问题对应的群体行为的波动性高,正的外在性对选择具有一定的锁定作用而能在一定程度上降低行为选择的混乱性;而正的外部性、高的决策敏感系数和高的社会效用系数是群体行为垄断性发生的条件。不同类型的社会网络对群体行为动力学的影响在于,随机网络中短的平均路径和无标度网络中枢纽节点的作用能够加速社会信号的传递从而加强社会外在性的作用。以上研究为现实中的各种群体现象,如时尚追逐、品牌忠诚等给予很好的解释和指导。

英文摘要：

The emergence of group behavior has long been an interested issue for many sociologists.Individual decision-making is usually affected by its observation or expectation of others＇,which is called externality.Based on the study of such externality,this paper sets up utility models and researches the collective dynamics by multi-agent simulation in deferent types of complex network.The researches show that groups with low decision-making sensitivity conduct high behavior chaos,and positive externality has a ＂lock in＂ effect for binary decision that can reduce the collective behavior chaos to a certain extent.While positive external,high-sensitive decision-making factors and high social utility coefficient are the necessary conditions for collective behavior monopoly.As to the impact of different types of social network to the collective dynamics,the short average path of the SW network or hub node in the SF network can speed up the transmission of social signals in turn will strengthen the external effect.These researches above can provide a theoretical support to the national public safety and public emergency management.