Environmental regulations have consistently been found to spur innovation in "clean" technologies, with one significant exception. Past cap-and-trade programs have encouraged adoption of existing pollution control technologies, but had little effect on innovation. Several explanations have been...

We study how opening to trade affects economic growth in a model where heterogeneous firms can choose to adopt a new technology already in use by other firms. We characterize the growth rate using summary statistics of the profit distribution--the ratio of profits between the average and...

The paper investigates the mechanics through which novel technological principles are developed and diffused throughout an economy consisting of a technologically heterogeneous ensemble of firms. In the model entrepreneurs invest in the discovery and in the diffusion of a technological principle...