Technical Efficiency Evaluation: Naturally Dual!

We provide a dual perspective on technical efficiency evaluation, in two respects. First, we build on the price assumptions implicitly associated with the notion of technical efficiency in a general equilibrium framework to characterize a set of appropriate references to be used in the technical efficiency evaluation of an inputoutput vector. Some existing evaluation methods always select an element of this set, but other methods fail to do so. Second, the above framework leads us to assert that a well-grounded measure of technical efficiency is naturally decomposable. One part refers to technical efficiency as captured by the classical Debreu-Farrell measure. The other part refers to technical efficiency resulting from the “implicit allocative efficiency” or “mix efficiency” of the evaluated vector. We present both a quantitybased distance measure and its price-based equivalent to evaluate this complementary dimension of technical efficiency. This generalized perspective encompasses the standard Debreu-Farrell framework for technical efficiency evaluation, and makes it fully consistent with the well-established Koopmans efficiency notion.