Empirical work on the wage impact of training has noted that unobserved heterogeneity of training participants should play a role. The expected return to training, which partly depends on unobservable characteristics, is likely to be a crucial criterion in the decision to take part in training...

Increasing energy efficiency is one of the main goals in current German energy and climate policies. We study the determinants of energy efficiency in the German manufacturing sector based on official firm-level production census data. By means of a stochastic frontier analysis, we estimate the...

This paper considers training, mobility decisions and wages together to test for the specificity of human capital contained in continuing training courses. We empirically analyse the relationship between training, mobility and wages in two ways. First, we examine the correlation between training...

In this paper, human capital investments are evaluated by assuming heterogeneous returns to education. We use the potential outcome approach to measure the causal effect of human capital investments on earnings as a continuous treatment effect. Empirical evidence is based on a sample of West...