"During the late eighteenth century, innovations in Europe triggered the Industrial Revolution and the sustained economic progress that spread across the globe. While much has been made of the details of the Industrial Revolution, what remains a mystery is why it took place at all. Why did this...

In the following we propose a growth model for an economy consisting of firms which are heterogeneous in technologies and input demands. We show that the growth rate in this economy depends not only on changes in the aggregate level of capital and labor, but also on changes in the allocation of...