Environmental efficiency under weak disposability: an improved super efficiency data envelopment analysis model with application for assessment of port operations considering NetZero

Because port operations have rapidly been extending, air pollution resulted from ports has increased and become a persistent concern for environmentalist policy makers. The objective of this paper is to measure the environmental efficiency in Korea. main characteristic assessment problem that undesirable output carbon dioxide (CO2) emissions exogenous fixed input terminal area should concurrently be considered. By analysing impacts outputs on decision making units (DMUs) performance, super slacks-based data envelopment analysis (SE-SBM-DEA) approach proposed. proposed consists two models: (SBM) model SBM (SE-SBM) model. models effectively discriminate between efficient inefficient ports, rank their efficiencies. To restrict any decreases or increases levels, slacks inputs are removed target functions relevant constraints approach. In addition, formulated according weak disposability assumption, so they can only reduced with reduction certain desirable outputs. Hence, its slack also SE-SBM models. As result, scalar measures deal discretionary DMU being evaluated. We examine applicability approach, using real data, 19