Rough Set Based Attribute Reduction and Extension Data Mining

In the data base of information system, usually there are some attributes which are unimportant to the decision attribute, and some records that disturb the decision making. In this paper, reducing the condition attributes based on the matter-element theory and rough set method, calculating the importance to the decision attribute for each condition attribute after reduction, and data mining the association rules based on the reduced attributes, then extension transforming the rules according the importance of each attribute, that come up with more reliable knowledge of extension transformation and more effective solutions.