On efficiency of Data Envelopment Analysis

In this paper, we suggest a new concept of "Value Free Efficiency" which does not introduce any value judgment for outputs and inputs. That is, similarly to the usual multiple criteria decision analysis, a Decision Making Unit (DMU) is defined to be efficient if there is no unit that consumes less inputs and produces more outputs than the DMU. In addition, we propose a generalized DEA model for estimating value free efficiency, ratio value efficiency proposed by Charnes, Cooper and Rhodes [4], and sum value efficiency proposed by Belton [2] and Belton and Vickers [3] as special cases. An illustrative example compares these concepts of efficiency.