Fifteen years after German reunification, the facts about slow regional convergence have born out the prediction of Barro (1991), except that migration out of East Germany has not slowed down. I document that in particular the 18-29 year old are leaving East Germany, and that the emigration has...

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 develop a new methodology for quantifying the tasks undertaken within occupations using 3,000 verbs from around 12,000 occupational descriptions in the Dictionary of Occupational Titles (DOTs). Using micro-data from the United States from 1880-2000, we find an increase in the employment share...

We develop a versatile general equilibrium framework to determine the spatial distribution of economic activity on any surface with (nearly) any geography. Combining the gravity structure of trade with labor mobility, we provide conditions for the existence, uniqueness, and stability of a...

Faster technological progress has long been considered a key potential benefit of agglomeration. Physical proximity to others may help inventors adopt new ideas in their work by increasing awareness about which new ideas exist and by enhancing understanding of the properties and usefulness of...

This paper develops a quantitative model of internal city structure that features agglomeration and dispersion forces and an arbitrary number of heterogeneous city blocks. The model remains tractable and amenable to empirical analysis because of stochastic shocks to commuting decisions, which...

According to national accounts data, value added per worker is much higher in the non-agricultural sector than in agriculture in the typical country, and particularly so in developing countries. Taken at face value, this "agricultural productivity gap" suggests that labor is greatly misallocated...

We document substantial within-country (cross-municipality) differences in incomes for a large number of countries in the Americas. A significant fraction of the within-country differences cannot be explained by observed human capital. We conjecture that the sources of within-country and...

This paper examines city formation in a country whose urban population is growing steadily over time, with new cities required to accommodate this growth. In contrast to most of the literature there is immobility of housing and urban infrastructure, and investment in these assets is taken on the...

Will improvements in information technology eliminate face-to- face interactions and make cities obsolete? In this paper, we present a model where individuals make contacts and choose whether to use electronic or face-to-face meetings in their interactions. Cities are modeled as a means of...