Filippini, Massimo; Tosetti, Elisa - 2014
In this paper we propose a general approach for estimating stochastic frontier mod- els, suitable when using long panel … large, cross sectionally correlated, non-stationary panel data models to estimate the frontier function. Given the long time … span of the panel, we investigate whether the variables, including the unobservable common factors, are non-stationary, and …