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Panel estimators and the identification of firm-specific efficiency levels in parametric, semiparametric and nonparametric settings
Sickles, Robin C., (2005)
A nonlinear multivariate error components analysis of technology and specific factor productivity growth with an application to the U.S. airlines
Sickles, Robin C., (1985)
A nonlinerar multivarite error components analysis of technology and specific factor produktivity growth with an application to the U.S. airlines