Study on condition attributes and decision attribute based on rough sets theory

The attributes of rough set play an important roles in rough theory. We discussed attribute subdivision in this paper. In the attribute subdivision we mainly research the relationship between attribute subdivision and the upper approximation, lower approximation, quality of approximation classification, accuracy of approximation classification, number of decision rules and relative reduction. Meanwhile, the qualities of non-redundant and redundant attributes are analyzed. In the decision subdivision, the attribute subdivision and decision subdivision are studied in the same decision table. Finally, an example is shown to understand the above properties. The research is helpful for the attribute reduction, formation of decision rules and enhancing confidences of decision rules.