۱٫ Introduction

۲٫ Preliminaries

۳٫ U* V-Type Double-Domain Fuzzy Order Variable Precision Rough Set

۴٫ Uncertainty Measure of U* V-Type Double-Domain Fuzzy Order Variable Precision Rough Set

۵٫ An illustrate Example

۶٫ Conclusion

۷٫ Acknowledgement

۸٫ References

Aiming at the problem that the U × V-type double-domain rough set can’t deal with fuzzy data in the past, this paper firstly established the variable precision rough set model on the basis of U × V-type double-domain rough set,and made an in-depth study on the upper approximation set and the lower approximation set of this model.Then the variable precision rough set model of U × V-type double-domain fuzzy order information system is established by introducing the U × V-type double-domain fuzzy dominance relation, and its related properties are discussed.The uncertainty measures are studied by defining the U × V-type double-domain fuzzy order precision rough set roughness and rough entropy. The conclusions are that as the precision threshold increases, its roughness and roughness entropy decrease gradually. These conclusions are verified by an example, which provides a theoretical basis for further revealing the uncertainty measure law of U × V-type double-domain fuzzy order variable precision rough set.

Introduction

With the rapid development of the real society, the complex data acquired in many fields has made the Pawlak rough set insufficiency in many aspects. For example, the object in question is always on the same domain set, but the problem to be solved in reality is cannot be described by a domain.Another example is that the knowledge or concept that people come into contact with in practical problems is vague and uncertain, and knowledge or concept cann’t be described with precise knowledge, such as medical diagnosis problems, one disease corresponds to multiple symptoms, and one symptom is manifested in multiple diseases. This problem obviously cannot be described by a domain domain, and a precise definition cannot be used to express the severity of diseases and conditions.Therefore, many scholars have established a rough set model of two universes by extending the single domain to the double-domain [6-9], and some scholars have extended the exact set to the fuzzy set and established the fuzzy rough set model [10- 11].