The last two decades have witnessed a revival in interest in the measurement of productive efficiency pioneered by (1957) and (1951). 1978 was a watershed year in this revival with the christening of DEA by (1978) and the critique of Farrell technical efficiency in terms of axiomatic production...

In this paper we show that in order to aggregate individual efficiency scores into a group (e.g., industry) efficiency score, in such a way that the multiplicative structure of further decompositions is preserved with equal weights across components, the weighted geometric mean is required. We...

In this paper we propose new aggregate or ‘group’ primal and dual scale elasticity measures of an economic system (e.g., industry consisting of several firms, etc.). The main contribution of the paper is that we show under what assumptions a formal relationship between these new aggregate...