A Research Of Some Problems In Qualitative Multiple Attribute Decision Making Environment

With the development of the socioeconomic environment, the decision making problems are more and more complexity, and the decision making information is fuzzier. It is more human to let decision makers express their preference information in their own words. So the research of multiple attribute decision making has changed from quantitative to qualitative environment. Up to now, there have been extension principle method, symbolic method,2-tuple method and direct operation method to aggregate linguistic information. For the former two methods, the results usually do not exactly match any of the initial linguistic terms; just an approximation process is developed to express the result in the initial expression domain. This produces the consequent loss of information and the operations are complex.2-tuple method expresses linguistic information by2-tuples, and uses fuzzy linguistic representation model aggregate linguistic information. While the results of the fourth one may go beyond the boundary of linguistic terms set, and can not compare the results which go beyond the boundary.In the process of decision making, the tradition of utility theory, conjoint measurement theory and game theory usually characterize the global preference relation on the set of alternatives. Generally, the min and max operations are employed to compare the vectors. But they have not satisfied compensatory and Pareto-optimal. Therefore, the researches of this thesis are as follows:Some new linguistic operations are defined based on the ideas of triangular norm and triangular co-norm. Then the OWA and OWGA operators are developed to the continuous linguistic environment, and propose linguistic disjunction (ELOWA) operator and linguistic conjunction (ELOGWA) operator. Some of their properties are studied. Based on the new aggregation operators, two methods of multiple attribute group decision making are proposed in linguistic environment.The qualitative scale is induced to a qualitative-quantitative set. Based on the ideas of triangular norm and triangular co-norm, some new qualitative-quantitative operations are defined. Then based on the numerical encoding of certain mapping, some new aggregation operations are developed to refine the min, max and Prioritised maximum operators, and their properties are studied to prove their efficiency and rationality. A new method of multiple attribute decision making about qualitative information is given to illustrate the refinements.