Granular Space Reduction to aβMultigranulation Fuzzy Rough Set
Multigranulation rough set is an extension of classical rough set, and optimistic multigranulation and pessimistic multigranulation are two special cases of it.βmultigranulation rough set is a more generalized multigranulation rough set. In this paper, we first introduce fuzzy rough theory intoβmultigranulation rough set to construct aβmultigranulation fuzzy rough set, which can be used to deal with continuous data; then some properties are discussed. Reduction is an important issue of multigranulation rough set, and an algorithm of granular space reduction toβmultigranulation fuzzy rough set for preserving positive region is proposed. To test the algorithm, experiments are taken on five UCI data sets with different values ofβ. The results show the effectiveness of the proposed algorithm.