中文摘要：

【目的/意义】致力于丰富在线群体的研究体系,本文引入系统思想的启示,创新地通过观测社会系统响应函数趋势来定性判断话题的驱动力和传播性,以此将在线群体分成四类,即外源性首要传播型、外源性次要传播型、内源性首要传播型和内源性次要传播型。【方法/过程】运用扎根理论和网络志方法,利用多案例研究法的思路,创新性地从个体成员参与的角度切入,探索内源动力在线群体的形成契机和成长轨迹。【结果/结论】本研究聚焦在个体的不同参与阶段。围绕首要传播型话题和次要传播型话题分别提出模型来揭示其形成过程。并且,通过与讨论外源动力话题的在线群体对比,归纳出不同种类话题的动力来源和传播力对群体形成的影响。

英文摘要：

【Purpose/significance】Devoted to enriching the research system of online group and inspired by the systematicthought, this article uses a new qualitative method of online topic classification based on observing the trend of a social sys-tem response function to judge topic dynamic source and propagation force. Through this method, online topic can be divid-ed into exogenous critical topic, exogenous subcritical topic, endogenous critical topic and endogenous subcritical topic.【Method/process】We conduct this research by combining grounded theory and netnography as well as studying several cas-es, and explore the endogenous online group formation motivation and growth track from the innovative perspective of en-gagement of individual member.【Result/conclusion】This paper focuses on the different stages of individual participation.we elaborate the online group formation mechanism and reveal its process by constructing two models based on endogenouscritical topic and endogenous subcritical topic respectively. What＇s more, by comparing with the online groups based on ex-ogenous topic, we discover the influence of different kinds of topics＇ power source and propagation force of group formation.