Determination of the development level rankings of geographical regions in Türkiye using multi-criteria decision-making

Determination of regional development levels provides essential contributions to the identification of imbalances between regions and the formulation of strategies to eliminate these imbalances. To ensure a sustainable and balanced development in the country, the criteria that the regions should have are expected to be at a level close to each other throughout the country. In this respect, this study, which analyses the development status of the regions in Türkiye, aims to contribute to the achievement of the targeted development goals by basing future strategies on the right foundations. In the study, the data on the regions' development status are obtained from official TurkStat sources, and the regions are evaluated within the framework of specific criteria. Since the development phenomenon is a wide-ranging issue, this study includes 51 criteria covering various dimensions such as social, economic, and demographic. Expert opinions were utilized in determining the importance levels of these criteria, and weights were calculated using the Analytical Hierarchy Process (AHP) method. In the analysis of the results, three different Fuzzy TOPSIS variations were used to evaluate Türkiye's inter-regional development levels: Triangular Fuzzy TOPSIS, Trapezoidal Fuzzy TOPSIS, and Intuitionistic Fuzzy TOPSIS. Fifty-one criteria were assessed in terms of 12 Level regions of Türkiye. According to the results of Triangular Fuzzy and Trapezoidal Fuzzy TOPSIS methods, Istanbul ranked first in development. Istanbul is followed by the Aegean, Mediterranean, Western Anatolia, Eastern Marmara, Southeastern Anatolia, Western Marmara, Central Anatolia, Western Black Sea, Middle Eastern Anatolia, Northeastern Anatolia, and Eastern Black Sea regions. This ranking reflects the performance of the regions in terms of economic, social, environmental, demographic, health, education, transport, crime, energy, and enterprise criteria. The results showed that Türkiye's regional development levels could be comparatively evaluated by using (Multi-Criteria Decision Making) MCDM methods. In addition, the fuzzy logic-based structures of the techniques used enabled the effective management of uncertainties in the decision-making process. They made it possible to make more precise regional assessments. These findings represent a valuable resource for policymakers, professionals, and academics working in the fields of sustainable development, multi-criteria decision making and regional development analysis. Furthermore, they serve as an important guide in determining regional development policies and efficient allocation of resources by facilitating decision-making processes in policy development, implementation, resource allocation, and utilization at national and local levels.