The concept of trapezoidal valued hesitant fuzzy set is introduced. Notion for distance between any two trapezoidal valued hesitant fuzzy elements is given. Using this proposed distance measure, we extend the technique for order preference by similarity to ideal solution for trapezoidal valued hesitant fuzzy sets. An example is constructed to show usefulness of this extension for multicriteria ...

In this paper the ranking method for intuitionistic fuzzy numbers is studied. The authors first define a possibility degree formula to compare two intuitionistic fuzzy numbers. In comparison with Chen and Tan’s score function, the possibility degree formula provides additional information for the comparison of two intuitionistic fuzzy numbers. Based on the possibility degree formula, the author...

Aggregation of fuzzy relations in multicriteria decision making problems is considered. Pair wise comparisons between the alternatives by several criteria are given as fuzzy relations with definite properties. The weighted coefficients of the criteria are fuzzy numbers. The aim is to suggest models for aggregation of the fuzzy relations taking into account the criteria importance. The propertie...

The paper presents models and corresponding algorithms for solving fuzzy multicriteria decision making problems. The models use or transform the initial information to fuzzy preference relations by each criterion. These relations possess required properties to solve the problems of choice or ordering of the alternatives. The weights of the criteria are real numbers or weighting functions.

We elaborate further on the reasons for the lack of equality between interval weighted averages and interval-based convex sums and highlight its consequences on the cogency of multicriteria decision evaluation procedures based on the use of fuzzy interval weights.

This paper presents a fuzzy optimization model to solve multicriteria decision making (MCDM) systems based on a fuzzy analytic hierarchy process (fuzzy AHP). To deal with the imprecise judgments of decision makers, a fuzzy AHP decision making model is proposed as an evaluation tool, where the expert’s comparison judgments are translated into fuzzy numbers. Unlike the conventional fuzzy AHP meth...

Aggregation of fuzzy relations on alternatives with the help of aggregation operators is considered in two cases: – the weighted coefficients of the criteria are not present in the mathematical formula of the aggregation operators; – a fuzzy preference relation between the criteria importance is given. The main result consists in proving the properties of the aggregated relation in dependence w...

A new accuracy function for the theory of interval-valued intuitionistic fuzzy set, which overcomes some difficulties arising in the existing methods for determining rank of interval-valued intuitionistic fuzzy numbers, is proposed by taking into account the hesitancy degree of interval-valued intuitionistic fuzzy sets. By comparing it with several proposed accuracy functions, the necessity and...