On the relative efficiency in general network structures

Data Envelopment Analysis (DEA) is an efficiency measurement tool for evaluation of similar Decision Making Units (DMUs). In DEA, weights are assigned to inputs and outputs and the absolute efficiency score is obtained by the ratio of weighted sum of outputs to weighted sum of inputs. In traditional DEA models, this measure is also equivalent with relative efficiency score which evaluates DMUs in compare with the most efficient DMU. Recently network DEA models are appeared in the literature, which try to assess DMUs regarding their internal production divisions and intermediate products. In this paper we compare absolute and relative efficiency scores in network framework. Since in network DEA models, an efficient DMU does not exist necessarily, the relative efficiency model helps us to have at least one efficient DMU in our assessments.

Network DEA; Absolute efficiency; Relative efficiency; Divisional efficiency; Overall efficiency.