一种Rough集相对约简的计算方法

A Calculation Method for Relative Reductions of Rough Sets

本文引入邻域分明合取项集概念,讨论了邻域分明合取项集的计算方法。在此基础上,利用约简集 RED_Q(U—{x_o},P)计算约简集 RED_Q(U,P)的思想,给出了相对约简的判定定理,从而提出了一种相对约简的计算方法。由于该方法不用计算分明矩阵的中间环节,节省了空间和时间,提高了运行效率。实验结果表明,该约简算法在效率上较现有的约简算法有一定提高。

In this paper, a new concept of neighbor discernible A-clauses set is introduced, a calculation method for neighbor discernible ∧-cclauses set is given, and a judgement theorem for relative reduction is obtained, calculating the relative reductions REDQ （U, P） based on the relative reductiond REDQ （U- {x0 }, P）, from which an calcuation method for all relative reductions of rough set is proposed. Since it doesn＇t need to generate the medial llnk of discernible matrix, so it can spare space and time and raise the run effieiency of the calculation method. The experimental results show that the algorithm is efficient in comparison with that-of the existing algorithms.