Feature selection is the pretreatment of data mining. Heuristic search algorithms are often used for this subject. Many heuristic search algorithms are based on discernibility matrices, which only consider the differe...Feature selection is the pretreatment of data mining. Heuristic search algorithms are often used for this subject. Many heuristic search algorithms are based on discernibility matrices, which only consider the difference in information system. Because the similar characteristics are not revealed in discernibility matrix, the result may not be the simplest rules. Although differencesimilitude（DS） methods take both of the difference and the similitude into account, the existing search strategy will cause some important features to be ignored. An improved DS based algorithm is proposed to solve this problem in this paper. An attribute rank function, which considers both of the difference and similitude in feature selection, is defined in the improved algorithm. Experiments show that it is an effective algorithm, especially for large-scale databases. The time complexity of the algorithm is O（｜ C ｜^2｜U ｜^2）.展开更多
ON August 8,2014 the AllChina Federation of Industry&Commerce published the list of China’s Top 500 Private Enterprises.Fifty-four private companies from Shandong Province ranked among the top 500,putting Shandon...ON August 8,2014 the AllChina Federation of Industry&Commerce published the list of China’s Top 500 Private Enterprises.Fifty-four private companies from Shandong Province ranked among the top 500,putting Shandong in third place behind Zhejiang and Jiangsu.Fifteen Shandong companies ranked in the top 100.This achievement is attributed to the province’s economic reforms and an improving business environment.展开更多
基金Supported by the National Natural Science Foundation of China (90204008)Chen-Guang Plan of Wuhan City(20055003059-3)
文摘Feature selection is the pretreatment of data mining. Heuristic search algorithms are often used for this subject. Many heuristic search algorithms are based on discernibility matrices, which only consider the difference in information system. Because the similar characteristics are not revealed in discernibility matrix, the result may not be the simplest rules. Although differencesimilitude（DS） methods take both of the difference and the similitude into account, the existing search strategy will cause some important features to be ignored. An improved DS based algorithm is proposed to solve this problem in this paper. An attribute rank function, which considers both of the difference and similitude in feature selection, is defined in the improved algorithm. Experiments show that it is an effective algorithm, especially for large-scale databases. The time complexity of the algorithm is O（｜ C ｜^2｜U ｜^2）.
文摘ON August 8,2014 the AllChina Federation of Industry&Commerce published the list of China’s Top 500 Private Enterprises.Fifty-four private companies from Shandong Province ranked among the top 500,putting Shandong in third place behind Zhejiang and Jiangsu.Fifteen Shandong companies ranked in the top 100.This achievement is attributed to the province’s economic reforms and an improving business environment.
