Using lexicographic parametric programming for identifying efficient units in DEA

In this paper, we propose the use of lexicographic parametric programming to recognize efficient units in Data Envelopment Analysis (DEA). By using the parameterization of the rhs vector of the envelopment problem, we obtain the efficiency curve which is traversing through the efficient frontier from unit to unit. The units in the basis with any parameter value are efficient and the unit dominated by a point on an efficient facet is inefficient. The second objective is needed to check that efficient curve on the boundary of the efficient frontier stays on the boundary.