元素最小描述并集下的多粒度覆盖粗糙集模型

摘要

To generalize multigranulation rough sets to a covering⁃based approximation space, this paper proposes three kinds of covering⁃based multigranulation rough sets by employing the conditional probability between the target concept and the union of the minimal descriptions of elements. Based on new definitions, some basic properties of these models were investigated and their relationships with some existing covering⁃based multigranulation rough sets are revealed. The inter⁃relationship among the three new models is also explored. The discussions show that the pro⁃posed models are a special form of text model, as well as extensions of some existing covering⁃based multigranula⁃tion rough sets.%为了拓展多粒度粗糙集理论在覆盖近似空间上的研究，本文利用元素的最小描述并集并结合条件概率，提出了3种多粒度覆盖粗糙集模型。在模型定义基础上，本文研究了3种新模型的一些特有性质，探讨了新模型与一些已有模型的内在联系与区别，对3种新模型进行了比较。研究结果表明一些已有模型是本文模型的特殊形式，是已有模型的有效拓展。