The rough set theory approximates a concept by three regions, namely, the positive, boundary and negative regions. Rules constructed from the three regions are associated with different actions and decisions, which immediately leads to the notion of three-way decision rules. A positive rule makes a decision of acceptance, a negative rule makes a decision of rejection, and a boundary rule makes ...

Real-world decision making typically involves the three options of acceptance, rejection and non-commitment. Three-way decisions can be motivated, interpreted and implemented based on the notion of information granularity. With coarse-grained granules, it may only be possible to make a definite decision of acceptance or rejection for some objects. A lack of detailed information may make a defin...

The notion of three-way decisions was originally introduced by the needs to explain the three regions of probabilistic rough sets. Recent studies show that rough set theory is only one of possible ways to construct three regions. A more general theory of three-way decisions has been proposed, embracing ideas from rough sets, interval sets, shadowed sets, three-way approximations of fuzzy sets, ...

After the epidemic, all enterprises are faced with difficult decision about whether enterprise should resume work and production immediately, which is related to safety development of enterprises. The three-way decisions offer a novel study perspective solve this problem. Firstly, we describe some relevant attributes double hierarchy hesitant fuzzy linguistic term sets, construct information sy...