Kumbhakar, Subal; Lien, Gudbrand; Hardaker, J. - In: Journal of Productivity Analysis 41 (2014) 2, pp. 321-337
heterogeneity, heteroskedasticity and technical inefficiency. We applied these models to a single dataset from Norwegian grain …-invariant) and residual (time-varying) technical inefficiency. We found that efficiency results are quite sensitive to how …