This paper introduces endogenous and directed technical change in a growth model with environmental constraints. A unique final good is produced by combining inputs from two sectors. One of these sectors uses "dirty" machines and thus creates environmental degradation. Research can be directed...

We construct a model where the equilibrium organization of firms changes as an economy approaches the world technology frontier. In vertically integrated firms, owners (managers) have to spend time both on production and innovation activities, and this creates managerial overload, and...

We analyse an economy where managers engage both in the adoption of technologies from the world frontier and in innovation activities. The selection of high-skill managers is more important for innovation activities. As the economy approaches the technology frontier, selection becomes more...

This paper studies the conditions under which the scarcity of a factor (in particular, labor) encourages technological progress and technology adoption. In standard endogenous growth models, which feature a strong scale effect, an increase in the supply of labor encourages technological...