Multi-criteria decision making for sustainable supplier selection using the hybrid fuzzy-rough approach (Case study: Kurdistan gas company)

The evaluation information mainly relies on expert’s subjective judgment, which is imprecise and uncertain, and this issue is also true in the supplier selection. In order to improve and achieve reliable results, this study provides a systematic framework for selecting suppliers based on sustainability dimensions in which a hybrid fuzzy- rough AHP-WASPAS approach is proposed for sustainable supplier selection. The effectiveness of the proposed methodology is illustrated through its application in Kurdistan Gas Company supplier selection. First, the sustainable supplier selection criteria are determined by reviewing previous research. After screening the sustainable supplier selection criteria with the fuzzy Delphi method, AHP based on fuzzy rough numbers is used to determine the weights of criteria. Finally, a developed version of Waspas method, namely the Waspas method based on rough-fuzzy numbers, is introduced which can be applied in the environment of vague and uncertain decision making. This proposed approach is used to rank sustainable suppliers of Kurdistan Gas Company.