Abstract：An approach of base noun phrase (BaseNP) identification based on rough sets is proposed in this paper. It divides BaseNP identification into two ordinal subtasks: tagging and identification, and regards BaseNP tagging as a decision-making problem which can be solved in rough sets theory. So it characters feature reduction and rule optimization. In the paper, rough sets-based rule learning method and relevant algorithms are briefly introduced at first, the flow charts of BaseNP tagging and identification are then described, and the solution to the instance collision is put forward for improving the performance of BaseNP identification. The detailed experimental steps and results, and the comparison with some representative similar systems are given at last. According to the analysis of the results, the paper also points out the direction of further improvement of the approach.
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2006, Vol. 20 
