中文摘要：

在线品牌社群本质上是社会网络，而结构洞是社会网络中关系形成的关键节点。以产品知识为前因，研究成员嵌入在线品牌社群结构洞位置的原因以及结构洞位置对品牌社群承诺和品牌承诺的影响，同时探讨互依自我在产品知识与结构洞之间的调节效应以及品牌社群承诺在结构洞与品牌承诺之间的中介效应。通过网上调研平台“问卷星”收集500份有效问卷，采用自我中心网的关系数据，通过UCINET软件计算结构洞位置，再使用偏最小二乘法进行实证检验。研究结果表明，产品知识对结构洞位置的占据有正向影响，互依自我对产品知识与结构洞位置之间的关系起正向调节作用，结构洞位置通过品牌社群承诺的完全中介作用影响品牌承诺。研究结论在理解社会网络与在线品牌社群之间的关系方面具有理论意义，对于在线品牌社群建构社会网络具有实践意义。

英文摘要：

The nature of online brand communities is of social networking. However, not much research has paid attention to its nature. Because an online brand community is mainly composed of strangers, how they connect with one another is crucial to the development of the community. Thus, as a bridge among two or more stranger community members, the structural hole is the key point in the formation of the social networks in an online brand community. From the perspective of product knowledge, this research explored antecedents of structural hole position in a brand community and its impacts on brand community commitment and brand commitment. The moderating effect of interdependent self on the rela- tionship between product knowledge and structural hole was investigated. It also discussed the mediating effect of brand communi- ty commitment between structural hole and brand commitment. Based on related literature and logical deduction, four hypotheses were proposed. Hence, an empirical study was conducted to test these hypotheses. Five hu/adred of valid questionnaires were col- lected through the paid service provided by the Sojump. com, a famous online survey platform in China. As a kind of social net- work analysis software, the UCINET was employed to calculate the position of structural hole with the relational data reported by participants in self-ego networks. Then the value of structural hole was put into the final statistical model. All of the hypotheses were tested by the partial least square （PLS） modeling. The results show that： （~）product knowledge positively influences the e- mergence of structural holes, because product knowledge provides more chances for members to communicate with one another. Then it further develops as a bridge connecting one member with others ; ~）interdependent self exerts a moderating effect on the relationship between product knowledge and structural holes. As compared to independent self, interdependent self makes mem- bers more inclined to provide the question raisers with