Multi-granulation graded covering rough sets

The multi-granulation rough sets is a very important extension of the rough sets model in multi-granulation and distributed environments. By the combination of the multi-granulation rough sets and the covering rough sets, with the introduction of the concept of graded error, this paper develops the new multi-granulation rough sets model, called the multi-granulation graded covering rough sets (MGGCRS). Firstly, two types of multi-granulation graded covering rough sets models are constructed. It follows the research on the properties of the two types of MGGCRS models. Moreover, the relationships among the single-granulation graded covering rough sets model (SGGCRS) and the MGGCRS are explored.