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...

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...

This paper analyses whether strategic motives for patenting influence the characteristics of companies' patent portfolios. We use the number of citations and oppositions to represent these characteristics. The investigation is based on survey and patent data from German companies. We find clear...