User activity plays an important role in the operation of many kinds of websites. Significant progress has been made on user activity modeling by researchers in many kinds of Web information process fields, such as Web log mining, blogs social network analysis, etc. However, research on user activity in many interactive websites, such as bbs and discussion group websites, has not attracted much attention. On the other hand, the integration of software modules which are responsible for user activity analysis is also a critical issue. We propose a framework which can be easily implemented for the analysis of user activity on an interactive website. In the framework, user activity model is represented by a hidden Markov model (HMM), and the method for user interest computation is provided. User activity analysis tasks, such as user group discovery, can be performed in the framework. In the experiments, we investigate three interesting problems which are related with user interest and user activity. Experiment results show that the framework is helpful for user activity analysis and the proposed user interest can describe user activity on an interactive website well, hence it can be used as an effective measure in analyzing user activity. (C) 2008 Elsevier B.V. All rights reserved.
