An Integer Linear Program for Integrated Supplier Selection: A Sustainable Flexible Framework

In this paper an integer linear programming model (ILP) is proposed for supplier selection by integrating the various ranks obtained from multi-criteria decision making (MCDM) techniques such as AHP, Fuzzy AHP, TOPSIS, Fuzzy TOPSIS, IRP and weighted IRP. However, the ranks obtained not necessarily are same. Such variability in ranking leads to dilemma in finalizing the suppliers’ ranks. Hence, there is a need to integrate these ranks into one consensus ranking. Therefore, this paper is an attempt to model integer linear program using various ranks (same or different) obtained from MCDM techniques to provide final suppliers’ ranks having minimum total deviation with respect to the ranks obtained from various MCDM techniques. The proposed ILP takes care of sustainability and flexibility aspects associated with supplier selection. Under flexibility factors such as production flexibility, responsiveness, after sale support and engineering support are considered. Similarly, under sustainability factors criteria are considered to account for people (social responsibility, quality certification and cultural differences), planet (environment responsibility and carbon footprint) and profit (price of the product, financial health, tariff and taxes, logistics management cost).The working methodology of the proposed framework is illustrated through an industry based survey and a case study.