We investigate learning at the workplace. To do so, we use German administrative data that contain information on the entire workforce of a sample of establishments. We document that having more highly paid coworkers is strongly associated with future wage growth, particularly if those workers...

The rise in national industry concentration in the US between 1977 and 2013 is driven by a new industrial revolution in three broad non-traded sectors: services, retail, and wholesale. Sectors where national concentration is rising have increased their share of employment, and the expansion is...

Sea-level rise and ensuing permanent coastal inundation will cause spatial shifts in population and economic activity over the next 200 years. Using a highly spatially disaggregated, dynamic model of the world economy that accounts for the dynamics of migration, trade, and innovation, this paper...

We develop a model of human interaction to analyze the relationship between globalization and pandemics. Our framework provides joint microfoundations for the gravity equation for international trade and the Susceptible-Infected-Recovered (SIR) model of disease dynamics. We show that there are...

This paper quantitatively assesses the world's changing economic geography and sectoral specialization due to global warming. It proposes a two-sector dynamic spatial growth model that incorporates the relation between economic activity, carbon emissions, and temperature. The model is taken to...

Global warming is a worldwide and protracted phenomenon with heterogeneous local economic effects. In order to evaluate the aggregate and local economic consequences of higher temperatures, we propose a dynamic economic assessment model of the world economy with high spatial resolution. Our...

This paper proposes a simple theory of a system of cities that decomposes the determinants of the city size distribution into three main components: efficiency, amenities, and frictions. Higher efficiency and better amenities lead to larger cities, but also to greater frictions through...

We present a theory of spatial development. Manufacturing and services firms located in a continuous geographic area choose each period how much to innovate. Firms trade subject to transport costs and technology diffuses spatially across locations. The result is a spatial endogenous growth...

We propose a theory of task trade between countries that have similar relative factor endowments but may differ in size. Firms produce differentiated goods by performing a continuum of tasks, each of which generates local spillovers. Tasks can be performed at home or abroad, but offshoring...

We study a world with national external economies of scale at the industry level. In contrast to the standard treatment with perfect competition and two industries, we assume Bertrand competition in a continuum of industries. In this setting, many of the "pathologies" of the standard treatment...