Rough set theory and vague set theory are powerful tools for managing uncertain, incomplete and imprecise information. This paper extends the rough vague set model based on equivalence relations and the rough fuzzy se...Rough set theory and vague set theory are powerful tools for managing uncertain, incomplete and imprecise information. This paper extends the rough vague set model based on equivalence relations and the rough fuzzy set model based on fuzzy relations to vague sets. We mainly focus on the lower and upper approxima- tion operators of vague sets based on vague relations, and investigate the basic properties of approximation opera- tors on vague sets. Specially, we give some essential characterizations of the lower and upper approximation operators generated by reflexive, symmetric, and transi- tive vague relations. Finally, we structure a parameterized roughness measure of vague sets and similarity measure methods between two rough vague sets, and obtain some properties of the roughness measure and similarity measures. We also give some valuable counterexamples and point out some false properties of the roughness measure in the paper of Wang et al.展开更多
The paper draws comparison and analysis among present similarity measure methods in the case of similari-ty measures between Vague values, provides a new similarity measure method, of which discusses on the normalchar...The paper draws comparison and analysis among present similarity measure methods in the case of similari-ty measures between Vague values, provides a new similarity measure method, of which discusses on the normalcharacteristics, gives some relative character theorems. At the same time, it analyzes the application of fuzzy similari-ty measures in vague similarity measures and gives its normal forms such as similarity measures between Vague sets,between elements and their weighted similarity measures. Finally, vague entropy rule respectively aiming at twokinds of cases is approached and its corresponding vague entropy expressions is provided. The content of this paper isof practical significance in such fields as fuzzy decision-making, vague clustering, pattern recognition, data miningetc.展开更多
文摘Rough set theory and vague set theory are powerful tools for managing uncertain, incomplete and imprecise information. This paper extends the rough vague set model based on equivalence relations and the rough fuzzy set model based on fuzzy relations to vague sets. We mainly focus on the lower and upper approxima- tion operators of vague sets based on vague relations, and investigate the basic properties of approximation opera- tors on vague sets. Specially, we give some essential characterizations of the lower and upper approximation operators generated by reflexive, symmetric, and transi- tive vague relations. Finally, we structure a parameterized roughness measure of vague sets and similarity measure methods between two rough vague sets, and obtain some properties of the roughness measure and similarity measures. We also give some valuable counterexamples and point out some false properties of the roughness measure in the paper of Wang et al.
文摘The paper draws comparison and analysis among present similarity measure methods in the case of similari-ty measures between Vague values, provides a new similarity measure method, of which discusses on the normalcharacteristics, gives some relative character theorems. At the same time, it analyzes the application of fuzzy similari-ty measures in vague similarity measures and gives its normal forms such as similarity measures between Vague sets,between elements and their weighted similarity measures. Finally, vague entropy rule respectively aiming at twokinds of cases is approached and its corresponding vague entropy expressions is provided. The content of this paper isof practical significance in such fields as fuzzy decision-making, vague clustering, pattern recognition, data miningetc.
基金国家自然科学基金(the National Natural Science Foundation of China under Grant No.60564001)教育部留学回国人员科研启动基金(The Project-sponsoredby SRF for ROCS+1 种基金SEMChina under Grant No.教育司留[2004]527号)。
