Practical common weights scalarizing function approach for efficiency analysis

The flexibility in the choice of weights is both a weakness and strength of DEA approach. It is a weakness because deters the comparison among DMUs on a common base. This flexibility is also a strength, however, if a unit turns out to be inefficient even when the most favorable weights have been incorporated in its efficiency measure, then this is a strong statement and in particular the argument that, the weights are incorrect is not tunable.For dealing with this difficulty and assessment of all DMUs on the same scale, this paper is proposed to examine the application of MOLP approach (scalarizing function) for generating common set of weights under the DEA framework. There are other methods in the literature which are also able to generate common weights. A case taken from Kao and Hung (2005) is solved to investigate the differences among these methods and some conclusions are derived.However, the model proposed in this paper has the following advantages. Firstly, against general approaches in the literature which are based on solving nonlinear problems the proposed approach solve a linear problem (an MOLP model). Secondly, when common weights of the input/output factors are available, efficiency scores can be measured on the same scale. Moreover, all DMUs can be ranked in terms of a common base. Finally, the proposed method, simply and with appropriate modifications, can be generalized to the other DEA models