This paper reviews the empirical literature on rates of return on R&D and interprets the economic significance of these estimates using a semi-endogenous growth model with a calibrated knowledge production sector. We analyse how R&D subsidies, a reduction of entry barriers for start-ups and...

We argue theoretically and document empirically that aging leads to greater (industrial) automation, and in particular, to more intensive use and development of robots. Using US data, we document that robots substitute for middle-aged workers (those between the ages of (36 and 55). We then show...