Abstract: We study the number, size, and location of a firm’s plants. The firm’s decision balances the benefit of delivering goods and services to customers using multiple plants with the cost of setting up and managing these plants, and the potential for cannibalization that arises as their number increases. Modeling the decisions of heterogeneous firms in an economy with a vast number of widely distinct locations is complex because it involves a large combinatorial problem. Using insights from discrete geometry, we study a tractable limit case of this problem in which these forces operate at a local level. Our analysis delivers predictions on sorting across space for industries with many plants per firm. Compared with less productive firms, productive firms place more plants in dense high-rent locations and place fewer plants in markets with low density and low rents. Controlling for the number of plants, productive firms also operate larger plants than those operated by less productive firms. We present evidence consistent with these and several other predictions using U.S. establishment-level data.
Abstract: 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 the data at the 1° by 1° resolution for the entire world. Over a 200-year horizon, rising temperatures consistent with emissions under Representative Concentration Pathway 8.5 push people and economic activity northwards to Siberia, Canada, and Scandinavia. Compared to a world without climate change, clusters of agricultural specialization shift from Central Africa, Brazil, and India's Ganges Valley, to Central Asia, parts of China and northern Canada. Equatorial latitudes that lose agriculture specialize more in non-agriculture but, due to their persistently low productivity, lose population. By the year 2200, predicted losses in real GDP and utility are 6% and 15%, respectively. Higher trade costs make adaptation through changes in sectoral specialization more costly, leading to less geographic concentration in agriculture and larger climate-induced migration.
American Economic Review, 2018, 108(12): 3855-3890
Abstract: We provide theory and evidence that the elasticity of local employment to a labor demand shock is heterogeneous depending on the commuting openness of the local labor market. We develop a quantitative general equilibrium model that incorporates spatial linkages in goods markets (trade) and factor markets (commuting and migration). We quantify this model to match the observed gravity equation relationships for trade and commuting. We find that empirically-observed reductions in commuting costs generate welfare gains of around 3.3 percent. We provide separate quasi-experimental evidence in support of the model’s predictions using the location decisions of million dollar plants.
Abstract: We study the impact of intersectoral and interregional trade linkages in propagating disaggregated productivity changes to the rest of the economy. Using U.S. regional and industry data, we obtain the aggregate, regional and sectoral elasticities of measured total factor productivity, GDP, and employment to regional and sectoral productivity changes. We find that the elasticities vary significantly depending on the sectors and regions affected, and are importantly determined by the spatial structure of the economy. We use our calibrated model to perform a variety of counterfactual exercises including several specific studies of the aggregate and disaggregate effects of shocks to productivity and infrastructure. The specific episodes we study include the boom in California’s computer industry, the productivity boom in North Dakota associated with the shale oil boom, the disruptions in New York’s finance and real state industries during the 2008 crisis, as well as the effect of the destruction of infrastructure in Louisiana following hurricane Katrina.
Abstract: We develop a dynamic spatial growth theory with realistic geography. We characterize the model and its balanced-growth path and propose a methodology to analyze equilibria with different levels of migration frictions. Different migration scenarios change local market size, innovation incentives, and the evolution of technology. We bring the model to the data for the whole world economy at a 1° × 1° geographic resolution. We then use the model to quantify the gains from relaxing migration restrictions. Our results indicate that fully liberalizing migration would increase welfare about threefold and would significantly affect the evolution of particular regions of the world.
Abstract: This paper studies the impact of spatial frictions on Asia’s long-term spatial development. Using the framework provided in Desmet, Nagy, and Rossi-Hansberg (2016), we analyze the evolution of Asia’s economy and the relative performance of specific regions and countries. We then perform a number of counterfactual experiments and find that a worldwide drop in transport costs of 40% increases the present discounted value of real income by 70.7% globally and 78% in Asia. These figures are much larger than those found in standard quantitative trade models because they include dynamic effects and take into account intracountry transport costs. We also perform exercises in which we upgrade Asia’s road network or relax migratory restrictions between locations in Asia. These exercises emphasize the important role of spatial frictions in the development of Asia’s economy.
Abstract: This paper studies the recent spatial development of India. Services, and to a lesser extent manufacturing, are increasingly concentrating in high-density clusters. This stands in contrast with the United States, where in the last decades services have tended to grow fastest in mediumdensity locations, such as Silicon Valley. India’s experience is not common to all fast-growing developing economies. The spatial growth pattern of China looks more similar to that in the United States than to that of India. Our findings suggest that certain frictions are keeping medium-density places in India from growing faster.
Abstract: 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. We apply the model to study the evolution of the US economy in the last half-century and find that it can generate the reduction in the manufacturing employment share, the increased spatial concentration of services, the growth in service productivity starting in the mid-1990s, the rise in the dispersion of land rents in the same period, as well as several other spatial and temporal patterns.
Abstract: The equilibrium relationship between trade and the spatial distribution of economic activity is fundamental to the analysis of national and regional trade patterns, as well as to the effect of trade frictions. We study this relationship using a trade model with a continuum of regions, transport costs, and agglomeration effects caused by production externalities. We analyze the equilibrium specialization and trade patterns for different levels of transport costs and externality parameters. Understanding trade via the distribution of economic activity in space naturally rationalizes the evidence on border effects and the "gravity equation".