网络教学中的教师角色实证研究

An Empirical Study of the Roles of Online Teachers

在网络教学中，教师的职责主要通过发布帖子体现。本研究中，笔者首先利用Berge(1995)的教学性、管理性、社会性、技术性四维角色模型，通过对教师发布的帖子进行内容分析，对三位高校教师、两位中学教师的在线教学角色进行了研究，其中，各有一位高校教师和中学教师是第一次开展网络教学。研究发现，教学性角色和管理性角色是教师最重要的两个角色。同时，笔者还利用社会网络分析(SNA）方法，对包括教师和排除教师两种情况的交互网络进行了分析，独立样本t检验发现，当把教师从交互网络中排除出去后，密度差异和入度网络中心势的差异在统计学上达到显著，这说明教师在交互过程中具有重要的影响。对于出度网络中心势分析，排除中学教师后交互网络的降幅在70%以上。中学师生交互网络和高校新手教师交互网络呈现了更多的以教师为中心的特点，而有经验高校老师参与的师生交互网络体现了更多的以学生为中心的特点。最后，笔者指出了本研究所存在的局限，并对后续研究计划进行了讨论。

This paper describes the roles of online instructors in virtual learning environments. The authors have developed a coding scheme to capture the range and variety of instructional behavior as revealed in the content of instructors postings in five asynchronous online courses. This coding scheme is based on Berge's instructor roles classification: pedagogical， managerial， social， and technical（Berge，1995）. Two courses used for illustration are from high schools， while three are from institutions of higher education. One high school and one University teacher have no online teaching experiences. Because Berge’s model cannot test instructor’s influence when they interact with students， the authors took computer logs as input and used social network analysis (SNA) to process them with SNA software package NetMiner2.6 to study instructor’s roles when they interacted with students. Firstly， the authors investigated the distribution of pedagogical， managerial， social and technical activities across different courses and found that instructor messages contained more pedagogical and managerial codes than social and technical ones. Secondly， the authors investigated instructors’ influence using SNA method: one with the teachers and others without. Independent sample t-test shows that density difference and network centralization difference were statistically significant if the instructors were factored out. Teachers in high schools played more important roles in the interaction process and the interaction patterns showed teacher-centered characteristics， while in institutions of higher education， the interaction models showed more student-centered tendency， especially when the teachers have more online teaching experiences. At the end， the authors explained the limitation of the current study and plans for future research.