Weak Disposability in Integer-Valued Data Envelopment Analysis

Conventional data envelopment analysis (dea) models normally assume all inputs and outputs arereal valued and continuous. however in most application- related problems some inputs and outputscan only take integer values, also, both desirable and undesirable outputs can be generated (e.g.,the number of traffic accidents and deaths in a transportation system). in this paper the effiect ofundesirable outputs in integer dea model is discussed. the proposed model distinguishes weakdisposability of outputs imposing non-uniform abatement factor. compared with radial models, anon radial model that directly deals with slacks is developed to calculate efficiency for integer-valueddata set. an empirical application is used to illustrate the approach.