During the 1850s, land in U.S. farms surged by more than 100 million acres while almost 50 million acres of land were transformed from their raw, natural state into productive farmland. The time and expense of transforming this land into a productive resource represented a significant fraction...

We use anonymized and aggregated data from Facebook to explore the spatial structure of social networks in the New York metro area. We highlight the importance of transportation infrastructure in shaping urban social networks by showing that travel time and travel costs are substantially...

This paper studies the effect of transport infrastructure on the real exchange rate (RER) and reaches two relatively strong conclusions. First, while the list of robust determinants of the RER is not long, transport infrastructure belongs to that list. Many other potential determinants proposed...

We investigate the relationship between interstate highways and highway vehicle kilometers traveled (VKT) in US cities. We find that VKT increases proportionately to highways and identify three important sources for this extra VKT: an increase in driving by current residents; an increase in...

The importance of increments to an existing highway system depends upon their contributions to the accessibility provided by the existing network. Nearly 40 years ago, Mohring [1965] suggested this logic for planning optimal highway investment programs. He argued it could be implemented by...

This paper surveys the theoretical and empirical literature on the relationship between the spatial distribution of economic activity and transportation costs. We develop a multi-region model of economic geography that we use to understand the general equilibrium implications of transportation...

This paper estimates the effect of access to transportation networks on regional economic outcomes in China over a twenty-period of rapid income growth. It addresses the problem of the endogenous placement of networks by exploiting the fact that these networks tend to connect historical cities....

Previous work on transportation investments has focused on average impacts in high- and middle-income countries. We estimate average and heterogeneous effects in a poor continent, Africa, using roads and cities data spanning 50 years in 39 countries. Using changes in market access due to distant...

The state of Indiana set out to build a Mammoth system of canals, railroads, and turnpikes in 1836, after a decade of intense debate in which sectional rivalries prevented any state action. This paper investigates the role played by the adoption of an ad valorem property tax in ameliorating the...

In this paper, we examine the effect of changes in population density--urban sprawl--between 1970 and 2000 on BMI and obesity of residents in metropolitan areas in the US. We address the possible endogeneity of population density by using a two-step instrumental variables approach. We exploit...