XU, Jin; ZERVOPOULOS, Panagiotis D.; QIAN, Zhenhua; … - In: Theoretical and Practical Research in Economic Fields III (2013) 2, pp. 124-131
The directional distance function model is a generalization of the radial model in data envelopment analysis (DEA). The directional distance function model is appropriate for dealing with cases where undesirable outputs exist. However, it is not a units-invariant measure of efficiency, which...
