Constructive methods of rough approximation operators and multigranulation rough sets

• DOI: 10.1016/j.knosys.2015.09.036
• Publication Date: 2015-10-19T21:21:21Z
• Authors: Xiaohong Zhang; Duoqian Miao; Caihui Liu; Meilong Le
• Keywords: 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology

Four kinds of constructive methods of rough approximation operators from existing rough sets are established, and the important conclusion is obtained: some rough sets are essentially direct applications of these constructive methods. Moreover, the new notions of non-dual multigranulation rough sets and hybrid multigranulation rough sets are introduced, and some properties are investigated.