entrepreneurship literature is that opportunities are exogenous, the most prevalent theory of innovation in the economics literature … opportunity by developing a knowledge spillover theory of entrepreneurship. The basic argument is that knowledge created … endogenously via R&D results in knowledge spillovers. Such spillovers give rise to opportunities to be identified and exploited by …

The intellectual breakthrough contributed by the new growth theory was the recognition that investments in knowledge … and human capital endogenously generate economic growth through the spillover of knowledge. Endogenous growth theory does … not explain how or why spillovers occur. The missing link is the mechanism converting knowledge into economically relevant …

dirty innovation and production; (ii) optimal policy involves both .carbon taxes. and research subsidies, so that excessive … the switch to clean innovation under laissez-faire when the two inputs are substitutes. Under reasonable parameter values …

effect of the composition of economic activity on innovation. We test whether the specialization of economic activity within … a narrow concentrated set of economic activities is more conducive to knowledge spillovers or if diversity, by bringing … together complementary activities, better promotes innovation. The evidence provides considerable support for the diversity …