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...

Unequal spatial distribution of economic activity within countries continues to be important despite the significant progress of the world economy during the second half of this century. Interest in spatial processes and inequalities has recently been revived by the influential work of Barro and...