IETT theme selection interval type-2 fuzzy AHP-TOPSIS hybrid model application

Since the same data expresses different meanings for different people, it is more accurate to explain them via fuzzy sets when comparing alternatives or criteria. Different methods and different linguistic terms are used to express fuzzy sets. There are many type-1 fuzzy AHP and type-1 fuzzy TOPSIS methods in the literature. In addition, interval type-2 AHP and interval type-2 TOPSIS methods have recently been introduced. The long-term 5-year strategic objectives of the IETT management system are; to increase employees' motivation, satisfaction and knowledge, to have a balanced and strong financial structure, to be sensitive to the environment, to apply new technologies, to improve the quality of service, to manage corporate knowledge and to increase the corporate reputation. In addition, there are annually changeable targets aiming to reach out developed results with themes such quality of service, strong financial structure, business and passenger safety, effective and productive processes etc. The purpose of the study is to present the interval type-2 fuzzy AHP method and the interval type-2 fuzzy TOPSIS method together utilizing the interval type-2 fuzzy sets. The interval type-2 fuzzy AHP and interval type-2 fuzzy TOPSIS methods were used together in the study. Selection was made among the twelve alternatives presented, taking into account the criteria provided in the balanced scorecard proposed by Kaplan and Norton in the selection of the IETT theme which was specifically addressed to help strategic choices.