Three-way decisions model based on tolerance rough fuzzy set

Based on Bayesian decision theory, three-way decisions model (TWDM) proposed by Yao gives new semantic interpretations of positive region, negative region and boundary region. Some extensions of TWDM have been proposed by different authors and have been successfully applied to many fields, such as soft computing, data mining and decision making. However existing three-way decisions models are almost developed in certainty environment, which limits their applications in uncertainty environment. In order to deal with this problem, based on tolerance rough fuzzy set, a TWDM is proposed in this paper. The main contributions of this paper include two aspects: (1) the tolerance rough fuzzy set which is extended from rough fuzzy set is introduced, and some basic properties of the tolerance rough fuzzy set are investigated. (2) The TWDM with respect to the tolerance rough fuzzy set is proposed. In addition, an example is given to illustrate the computation processes of the TWDM.