Productivity levels and productivity growth rates vary significantly over space. These differences are perhaps most pronounced between countries, but they remain acutely evident within national spaces as economic growth favors some cities and regions and not others. In this paper, we map the...

Productivity and wages tend to be higher in cities. This is typically explained by agglomeration economies, which increase the returns associated with urban locations. Competing arguments of specialization and diversity undergird these claims. Empirical research has long sought to confirm the...