efficiency of two-stage systems in presence of intuitionistic fuzzy data

Network data envelopment analysis (ndea) is a widely used method inorder to calculate the efficiency of systems with network structures. two-stage systemsare special cases of these systems that in the first stage consume inputs to produce intermediate measures. then, these systems in the second stage produce outputs by consuming intermediate measures. however, in real applications, inputs, outputs and intermediate measures of two-stage systems can be viewed as intuitionistic fuzzy numbers. hence, in this study we will propose a techniques that use the intervals of cut ,  cut , (, ) cutto measure the overall efficiency and efficiency of thestages in two-stage systems.