Class-based Rough Approximation with dominance principle

Dominance-based Rough Set Approach (DRSA), as the extension of Pawlak's Rough Set theory, is effective and fundamentally important in Multiple Criteria Decision Analysis (MCDA). In previous DRSA models, the definitions of the upper and lower approximations preserve the class unions rather than the singleton class. In this paper, we propose a new Class-based Rough Approximation with respect to different DRSA models including Classical DRSA model, VC-DRSA model and VP-DRSA model. In addition, we explore the new class-based reducts and their relations.