关键词: 信息传播模式, 复杂社会网络, 社会认知, 社会智能

Abstract: By comparing spread mechanism of infectious diseases with information transmission mechanism，this paper presents a mathematical model of information transmission mechanism in BBS.By modeling changes of the number of posts on topics in BBS，it analyzes features of information transmission mechanism in BBS，and utilizes actual data to illustrate and validate the features.The experimental results indicate that，although a lot of netizens are attracted by BBS，they are only interested in some topics and participate in the discussion；the growth rate of the number of posts on most topics（94.9%） increases first and then decreases to 0 while the growth rate of the number of posts on a few topics（5.1%） directly reduces to 0.These findings are helpful to understand information transmission mechanism in BBS and are instructive to control and manage the information transmission in BBS.

Key words: information transmission mechanism, social network, social cognition, social intelligence