Prioritising the location of gold refining facility in Nigeria: An application of advanced multi-criteria decision making methods based on Fermatean fuzzy sets

Abstract

Value addition to raw gold through refining is a means for enhancing economic growth and minimizing unemployment. However, the improper location of gold refining facility may hinder the inherent advantages in value addition chain. This study therefore proposed novel Fermatean fuzzy Spearman rank correlation coefficient (FF-SCC) multi criteria decision making (MCDM) method to prioritise the gold refining facility location in Nigeria. The objectives of the study are achieved through the identification of various states in Nigeria with gold deposits and those with proxy locations to the gold bearing states. Three indices under the sustainable development goals (SDGs) which are economic, environment and society form the bases of the evaluation criteria. Fifteen different states form the alternative while eight criteria formulated within the sustainable development goals indices are used for the evaluation. The importance of the criteria in relation to the alternatives was assessed by the group of three experts. The outcome of the proposed four FF-SCC based MCDM methods ranked Oyo and Osun states either the first- or second-best place to locate the gold refining facility while Kogi State and Sokoto are ranked least. The proposed models are validated with FF-VIKOR MCDM method and their rankings are also similar.