Trapezoidal bipolar fuzzy edas method for multi criteria group decision making problems and a real application

This thesis presents a novel trapezoidal bipolar fuzzy EDAS (TrBF-EDAS) method to handle Multi-Criteria Group Decision Making problems in which includes linguistic vagueness depending on double-sided judgmental thinking of the decision-makers. The proposed TrBF-EDAS is employed to conduct a real case dealing with the selection of a medical device which can perform image-based assays dealing with dead and live cell count, cell viability. In this regard, the selection process of the most desirable device to be used in cell culture studies in the biology department of the medical faculty in Turkey is performed with the proposed TrBF-EDAS by taking the opinion of three decision-makers who are experts in their fields. In the thesis, twenty-four cases are generated by assigning randomly different values to the weights of criteria to verify the validation of the proposed TrBF-EDAS. For all generated cases, the preference rankings obtained by the TrBF-EDAS are compared with the outputs obtained by the TrBF-TOPSIS, presented before in the academic literature. According to the comparisons, Spearman's rank correlation coefficients are found sufficiently satisfactory. Consequently, TrBF-EDAS, requiring relatively less effort compared with the TrBF-TOPSIS, is an efficient and robust tool to apply readily for evaluations of the alternatives in any system.