摘要
研究了优势关系下不协调决策表的下近似约简问题,引入新的下近似约简的定义,证明新的下近似约简与文献[7]定义的下近似约简等价。给出新的下近似约简的判定定理和辨识矩阵,与文献[7]的辨识矩阵相比,计算新的下近似约简的辨识矩阵的时间复杂度要低。因此,可以利用新的辨识矩阵来求决策表的下近似约简.
The lower approximation reduction in inconsistent decision table based on dominance relations is studied. The new lower approximation reduction is introduced and proved that it is equal to the lower approximation reduction which defined in [7]. The judgment theorem and discernibility matrix with respect to the new lower approximation reduction are established. Compare with the algorithm in [7], the time complexity of the algorithm for finding a discernibility matrix with respect to new lower approximation reduction is lower. So the new discernibility matrix can be used to find the lower approximation reduction.
出处
《大学数学》
2012年第6期51-55,共5页
College Mathematics
基金
湛江师范学院科研基金项目(L0602)
关键词
粗糙集
决策表
优势关系
下近似约简
辨识矩阵
rough set
decision table
dominance relation
lower approximation reduction
discernibility matrix
