Redefinition of Decision Rules Based on the Importance of Elementary Conditions Evaluation

Abstract

The paper presents an algorithm of decision rules redefinition that is based on evaluation of the importance of elementary conditions occurring in induced rules. Standard and simplified (heuristic) indices of elementary condition importance evaluation are described. There is a comparison of the results obtained by both indices concerning classifiers quality and elementary condition rankings estimated by the indices. The efficiency of the proposed algorithm has been verified on 21 benchmark data sets. Moreover, an analysis of practical applications of the proposed methods for biomedical and medical data analysis is presented. The obtained results show that the redefinition reduces considerably a rule set needed to describe each decision class. Additionally, after the rule set redefinition negated elementary conditions may also occur in new rules.