• Corpus ID: 8558306

Outlier Detection for Text Data : An Extended Version

  title={Outlier Detection for Text Data : An Extended Version},
  author={Ramakrishnan Kannan and Hyenkyun Woo and Charu C. Aggarwal and Haesun Park},
The problem of outlier detection is extremely challenging in many domains such as text, in which the attribute values are typically non-negative, and most values are zero. [] Key Method Our iterative algorithm TONMF is based on block coordinate descent (BCD) framework. We define blocks over the term-document matrix such that the function becomes solvable. Given most recently updated values of other matrix blocks, we always update one block at a time to its optimal.

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