This contribution points out a minor problem in the specifcation of technology when computing the Luenberger productivity indicator that has been hitherto ignored in the literature. The solution of this problem increases the likelihood that the directional distance functions underlying this...

The purpose of this contribution is to highlight an underexplored property of the directional distance function, a recently introduced generalization of the Shephard distance function. It diagnoses in detail the economic conditions under which infeasibilities may occur for the case of...