The duality between measures of economic and technical efficiency has been extensively studied in the productive efficiency analysis. This duality ensures a meaningful interpretation of technical efficiency as economic efficiency evaluated at the most favorable shadow prices. This paper concentrates on economic efficiency as short run profit efficiency. We first argue that a modified version of Varian's goodness-of-fit measure provides an appropriate economic efficiency measure in that context. Next, we show that a variant of the McFadden gauge function provides a natural dual efficiency measure for this short run profit efficiency measure. In particular, we establish two attractive properties of that technical efficiency measure: (i) it can be interpreted as Varian's profit efficiency measure evaluated at shadow prices; (ii) it provides an upper bound for profit efficiency
