Study On Multiple Attribute Decision Making Under Linguistic Environment

In the modern multiple attribute decision making, using uncertain information to express decision makers’ preferences is more and more popular. So far, fuzzy logic and fuzzy set theory have been successfully applied to handle uncertain multiple attribute decision making. The earlier fuzzy tool is suitable for the quantitative evaluation approach. However in decision making, due to the fuzziness and uncertainty of human mind, it is more reasonable that describe decision making information by natural language. Therefore, study on linguistic multiple attribute decision making has very important practical significance.So far, the methods of dealing with linguistic information has the following four categories:the first one is the method based on extension principle; The second is the symbolic method; Three is the 2-tuple fuzzy linguistic representation model; Four is to calculate the linguistic variables directly. Preceding two kinds of methods are easy to lose information in processing linguistic information, and lead to the result lack of ideal. The two latter methods in some cases may cause a counterintuitive phenomenon. In addition, the product of the real numbers and linguistic variables is lack of rationality and meaningless.In order to overcome some defects existing in the above methods, a fuzzy linguistic multiset is constructed. Some linguistic variables operational laws on this multiset are defined, a new qualitative aggregation operator ψ is proposed,the weighted arithmetic averaging (WAA) operator and the ordered weightedaveraging (OWA) operator are extended to linguistic environment. The linguisticmultiple attribute decision making problems are studied on this thesis, the maincontents are as follows: (1) Inspired by the 2-tuple fuzzy linguistic representation model, a fuzzylinguistic multiset is induced by linguistic term set. Based on T-norm andT-conorm, some new linguistic operational laws on the fuzzy linguistic multisetare defined, and their properties are studied. (2) On the basis of the operational laws on fuzzy linguistic multiset, usingthe maximizing deviations approach to obtain the weights of attributes. (3) Based on the operational laws on fuzzy linguistic multiset, the WAAoperator and the OWA operator are extended to linguistic environment, and thenthe ELWAA operator and the ILOWA operator are presented, some properties ofthe new operators are researched. Two new methods for linguistic multipleattribute decision making based on the ELWAA operator and the ILOWAoperator are given. (4) A new qualitative aggregation operator ψ is provided to handlelinguistic information; some good properties of this new operator areinvestigated. Based on the qualitative aggregation operator ψ, a new method forlinguistic multiple attribute decision making is given.