We study a model of endogenous growth where firms invest both in product and process innovations. Product innovations (that open up completely new product lines) satisfy the advanced wants of the rich. Subsequent process innovations (that decrease costs per unit of quality) transform the...

In this note, we construct two theoretical models that analyze the relationship between inequality of access and rates of innovation as well as correlative data that show a negative correlation between income inequality and levels of innovativeness. Our two models suggest that unequal access to...

We analyze the economic growth effects of rising longevity in a framework of endogenous growth driven by quality-improving innovations. We show that a rise in longevity raises savings and thereby reduces the market interest rate. Since the monopoly profits generated by a successful innovation...

We show that, in a model without commitment to future policies, geoengineering breakthroughs can have adverse environmental and welfare effects because they change the (equilibrium) carbon taxes. In our model, energy producers emit carbon, which creates a negative environmental externality, and...

The basic competitive model with freely available technology is suited for static industries but misleading as applied to major innovative economies for which development of new technologies equals in magnitude around 10% of gross domestic investment. We distinguish free generic technology from...