关键词: 变精度约简, 正区域约简, 辨析矩阵, 决策表, 粗糙集

Abstract: The positive region reduction and variable precision reduction for decision table are two important types of attribute reductions. By comparing the calculation process of the two discernibility matrices, under the condition that the variable precision threshold is greater than 0.5, the value of the decision attribute can be appropriately changed, so that the calculation of the variable precision reduction can be converted into the calculation of the positive region reduction. This paper shows that the calculation of any variable precision reduction can be transformed into that of a positive region reduction. This transformation can improve the efficiency of the variable precision reduction algorithm.

Key words: variable precision reduction, positive region reduction, discernibility matrix, decision table, rough set