In this paper, we study the properties of optimal growth models à la Nelson and Phelps (1966) where the labor resources of an economy can be allocated freely either to production, technology adoption or capital maintenance. We first characterize the balanced growth paths of a benchmark model...

We study an optimal growth model with one-hoss-shay vintage capital, where labor resources can be allocated freely either to production, technology adoption or capital maintenance. Technological progress is partly embodied. Adoption labor increases the level of embodied technical progress....