Comparative Analysis of Hybrid MCDM Methods for Supplier Evaluation: SWARA/AHP-Based MOORA and WASPAS Approach in the Turbocharger Industry

Turbocharger technology, a crucial component in vehicle engines, is utilized to optimize various critical factors such as performance, fuel efficiency, quality, cost, and environmental considerations. This article aims to compare the results of using hybrid multi-criteria decision-making (MCDM) methods in the supplier evaluation process of a company operating in the Netherlands that manufactures and distributes turbochargers and engines. During the weighting phase of the supplier selection (SS) criteria, established through a literature review and group decision-making with the purchasing department, analytic hierarchy process (AHP) and stepwise weight assessment ratio analysis (SWARA) are applied. In the phase of evaluation, multi-objective optimization by ratio analysis (MOORA) and weighted aggregated sum product assessment (WASPAS) methods are employed. The suppliers are evaluated and ranked using four different forms of MOORA and two different forms of WASPAS. Additionally, the suppliers’ rankings based on the hybrid methods are converted into overall performance scores using the Borda count and Copeland methods, and the suppliers are evaluated through sensitivity analyses across eight different scenarios. The implementation steps of these methods are presented algorithmically. This comparative case study is the first to analyze the supplier evaluation process using several forms of hybrid MOORA and WASPAS. The advantages and disadvantages of the hybrid methods used in the study are thoroughly examined. In this respect, the study can serve as a decision support mechanism for the company and other firms operating in similar industries to enhance the efficiency of their procurement processes.