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has been cited by the following article:

• TITLE: Clustering Student Discussion Messages on Online Forumby Visualization and Non-Negative Matrix Factorization

  AUTHORS: Xiaodi Huang, Jianhua Zhao, Jeff Ash, Wei Lai

  KEYWORDS: Online Forum; Cluster; Non-Negative Matrix Factorization; Visualization

  JOURNAL NAME: Journal of Software Engineering and Applications, Vol.6 No.7B, October 23, 2013

  ABSTRACT: The use of online discussion forum caneffectively engage students in their studies. As the number of messages posted on the forum is increasing, it is more difficult for instructors to read and respond to them in a prompt way. In this paper, we apply non-negative matrix factorization and visualization to clustering message data, in order to provide a summary view of messages that disclose their deep semantic relationships. In particular, the NMF is able to find the underlying issues hidden in the messages about which most of the students are concerned. Visualization is employed to estimate the initial number of clusters, showing the relation communities. The experiments and comparison on a real dataset have been reported to demonstrate the effectiveness of the approaches.