Human capital composition, R&D and the increasing role of services

We relate the negative correlation between income and the ratio of high to low-tech human capital and the positive correlation between income and investment on R&D, both present in developed countries, to the transition to a services economy. To this end a growth model with endogenous innovation and accumulation of high-tech and low-tech human capital is developed. We consider a negative effect of technological development on the accumulation of high-tech human capital and that services are relatively intensive in low-tech human capital. We confirm the model implications quantitatively in a calibration exercise.