Identifying the global reference set in DEA: A mixed 0-1 LP formulation with an equivalent LP relaxation

The recent study by [Mehdiloozad, Mirdehghan, Sahoo, & Roshdi (2015) On the identification of the global reference set in data envelopment analysis. EJOR, 245, 779-788] proposes a linear programming (LP) model for the problem of finding the global reference set (GRS) of the evaluated decision making unit (DMU). This technical note revisits the problem and reformulates it as a mixed 0-1 LP model. By applying the LP relaxation method, it then transforms the formulated model into an equivalent LP model. Finally, it shows that the resulting LP model is equivalent to the LP model of Mehdiloozad et al. (2015).