using malmquist productivity index in a two-stage sustainable supply chain

Data envelopment analysis (dea) is used as a tool to evaluate a set of decision-making units (dmus) forming a sustainable supply chain (ssc). furthermore, the malmquist productivity index (mpi) is used to determine the level of progress or regression in the dmus. in this paper, we calculate the mpi in a sustainable supply chain using non-radial dea models.therefore, a non-radial enhanced russell model in two-stage supply chain is proposed to determine the efficiency of each dmu by considering economic, social and environmental sustainability factors. thus, in this paper, mpi is calculated in a sustainable supply chain using the non-radial enhanced russell measure (erm). the proposed model considers the priority of decreasing inputs and increasing outputs by the decision-maker. moreover, our applied study involves an evaluation of sustainable supply chains in iranian oil refineries.