Statistical Evidence for Decision System Analysis
决策表分析的统计依据

The nonparametric test method is introduced to the reduction of decision table, which gives the statistical evidence for decision system analysis. Firstly, we transfer the raw decision system into a series of corresponding con- tingency table between each condition attribute and decision attribute; then, test the correlation significance between them to make sure if a condition attribute is useless and should be deleted. Secondly, for those condition attributes that are correlated with decision attribute, we do correlated measure using Lambda coefficient. The set of condition at- tributes that are correlated with decision attribute is regarded to be the reduction of condition attributes, and the cor- responding Lambda coefficient shows the proportionate reduction in error. At the same time, we get the first-order rules of the raw decision table based on the series of corresponding contingency table. Our test shows that our method is feasible and efficiently.