属性约简簇的优化选择

An Optimizing Selection in a Family of Attribute Reducts

属性约简是粗糙集的一个重要应用.一个数据集往往含有多个属性约简,人们一般用启发式算法找到其中的一个,再通过实验的方法验证其有效性.面对多个属性约简,人们往往难以区别,缺乏有效的手段选取最优或较优的属性约简.使用多种概念漂移的度量指标和信息损失的度量方法比较了同一个知识系统中不同Pawlak约简之间的区别与联系.提出了属性约简重心的概念,并研究其性质.实验结果显示,在众多的属性约简中,离重心最近的属性约简在分类准确率方面具有较大的优势.概念漂移的度量指标和信息损失的度量方法有助于区分不同的属性约简,属性约简的重心有助于在众多的属性约简中选择最优或较优的一个.

Attribute reduction is one of important applications in rough set theory.There are more than one attribute reduct in a data set,and heuristic algorithms are always used to find one of them,which is verified with experiments.For many attribute reducts,it is hard for people to distinguish them,and lacks of valid methods of selecting the best one or a better one.Indexes of concept drift and information loss are employed to compare the same type of Pawlak attribute reducts in a knowledge system.The focus of attribute reducts is presented,and its properties are investigated in this paper.Experimental results show that the closest attribute reduct to the focus of attribute reducts is better than other attribute reducts in classification accuracy.Indexes of concept drift detection and information loss can distinguish different attribute reducts,and the focus of attribute reducts can be employed to select the best attribute reduct or a better one.