We propose a two-stage procedure for finding realistic benchmarks for nonparametric efficiency analysis. On the first stage the efficient DMUs are figured out by a free disposal hull approach. These benchmarks are directly targeted by directional distance functions and the extent of inefficiency...

In this paper we report the results from a detailed investigation of the shifts of the world production frontier function over the period 1980-2010. Analogous to a radar we implement a novel measurement approach for these shifts using nonparametrically computed productivity measures to scan the...

We conduct an empirical analysis of the technical efficiency of cars sold in Germany in 2010. The analysis is performed using traditional data envelopment analysis (DEA) as well as directional distance functions (DDF). The approach of DDF allows incorporating the reduction of carbon dioxide...