This paper presents an application of the Generalised Error Correction Model (GECM) for heterogeneous factor demands based on the quadratic cost function. Using data for 26 West German manufacturing industries over the period 1976-1995, it turns out that less general specifications such as the...

This paper provides empirical evidence on both the magnitude and determinants of unfilled positions for information technology workers using cross-sectional data on 4150 German firms. Vacancies are defined as unfilled positions excluding those created by replacement needs during the first half...

This study deals with the determinants of factor demand in 27 industries of the manufacturing sector during the period 1978 to 1990. Using a quadratic cost function, six production factors are distinguished : capital, energy, three types of labour and intermediate materials. A parametric test of...

We present a new method for imposing and testing concavity of a cost function using asymptotic least squares, which can easily be implemented even for cost functions which are nonlinear in parameters. We provide an illustration on the basis of a (generalized) Box-Cox cost function with six...