The explicit role of weight bounds in models of data envelopment analysis

In this paper, we suggest that weight bounds used in models of data envelopment analysis (DEA) can be assessed using production trade-offs between inputs and outputs. This development is based on a transformation of the envelopment DEA model to a special form, which exhibits an explicit link between weight bounds and production trade-offs. This allows us to specify the guidelines to the construction of weight bounds, which ensure that the envelopment form has a clear economic meaning. In this development, the radial efficiency measure retains its standard meaning as a technologically realistic improvement factor. This contrasts with the methods based on value judgements for which this traditional meaning of efficiency becomes void. We show that the exact economic meaning of the same weight bounds depends on the unit under the assessment and the orientation (input-minimization or output-maximization) of the model. The suggested approach is valid under the assumptions of constant and variable returns to scale.