An Efficient Attribute Reduction Algorithm Based on Discernibility Object Pair Set
XU ZhangYan1,2, YANG BingRu1, SONG Wei1
1. School of Information Engineering, University of Science and Technology Beijing, Beijng 100083 2. Department of Computer, Guangxi Normal University, Guilin 541004
Abstract The definition of discernibility object pair set and the corresponding definition of attribute reduction are introduced. It is proved that the definition of attribute reduction is equivalent to the one based on positive region. Since U/C is important for computing the discernibility object pair set, an algorithm for computing U/C is designed, whose time complexity is cut down to O(｜C｜｜U｜). Under this condition, an efficient attribute reduction algorithm is proposed, whose time and space complexity are cut down to O(｜C｜｜U｜)+O(｜C｜(｜U/C｜2)) and O(｜U｜)+O(｜U/C｜2) respectively. Finally, an example is used to illustrate the efficiency of the new algorithm.
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2006, Vol. 19 
