Six sigma project selection using interval neutrosophic TOPSIS

Six Sigma approaches aim at providing almost defect-free products and/or services to customers. Six Sigma is a powerful and comprehensive management tool for meeting customer needs. Well-designed projects are capable to provide significant financial benefits, bring competitive advantage and increased customer satisfaction. Well-designed projects having clear and concise descriptions and objectives are capable to provide significant financial benefits, increased customer satisfaction and bring competitive advantage. Selecting Six Sigma improvement projects has been one of the most challenging and frequently discussed issues in the literature. Selecting the most useful project/s is a key success factor in Six Sigma approach. Selecting Six Sigma projects is a multi criteria decision making problem involving many tangible and intangible criteria under uncertainty. In this paper, uncertainty will be handled by neutrosophic sets. “A neutrosophic set deals with the origin, nature, and scope of neutralities, as well as their interactions with different ideational spectra” [1]. In neutrosophic sets, truth-membership, indeterminacy-membership and falsity-membership are all together included. Neutrosophic sets are accepted as a super set of the other types of sets such as classical sets, ordinary fuzzy sets, hesitant fuzzy sets, intuitionistic fuzzy sets, and soft sets. In this paper, we employ interval neutrosophic TOPSIS method to evaluate Six Sigma projects. By reviewing the literature, seven criteria e.g. total cost, required time and customer satisfaction are taken into account. To the best knowledge of the authors, this is the first study to evaluate Six Sigma projects using interval neutrosophic TOPSIS approach with group decision making.