The number of people buying and selling products online in China has grown from practically zero in 2000 to more than 400 million by 2015. Most of this growth has occurred in cities. In this context, the Chinese government recently announced the expansion of e-commerce to the countryside as a...

We explore the impact of rising incomes at the top of the distribution on spatial sorting patterns within large U.S. cities. We develop and quantify a spatial model of a city with heterogeneous agents and non-homothetic preferences for neighborhoods with endogenous amenity quality. As the rich...

We develop a methodology to estimate robust city level vehicular mobility indices, and apply it to 154 Indian cities using 22 million counterfactual trips measured by a web mapping service. There is wide variation in mobility across cities. An exact decomposition shows this variation is driven...

Tracking human activity in real time and at fine spatial scale is particularly valuable during episodes such as the COVID-19 pandemic. In this paper, we discuss the suitability of smartphone data for quantifying movement and social contact. We show that these data cover broad sections of the US...

This paper documents and explains the striking rise in the proclivity of college-educated individuals to reside near city centers. We show that this recent urban revival is driven entirely by younger cohorts in larger cities. With a residential choice model, we quantify the role of jobs,...

We assemble a new global database on motor vehicle travel speed in over 1,200 large cities in 152 countries. We then estimate comparable city-level indices of travel speed and congestion. Most of the variation in urban travel speed is across countries, not within. National income per capita...

Measuring changes in welfare, and particularly the price index, is challenging in the absence of well-measured prices covering the entire consumption basket. We propose and implement a new approach to estimate changes in income-group specific price indices and welfare using rich, but widely...

A growing literature has documented the role of firm heterogeneity within sectors in accounting for nominal income inequality. This paper explores the implications for household price indices across the income distribution. Using detailed matched US home and store scanner microdata, we present...

Tourism is a fast-growing services sector in developing countries. This paper combines a rich collection of Mexican microdata with a quantitative spatial equilibrium model and a new empirical strategy to study the long-term economic consequences of tourism both locally and in the aggregate. We...

Governments are making it a priority to upgrade information and communication technologies (ICT) with the aim to increase available internet connection speeds. This paper presents a new empirical strategy to estimate the causal effects of these policies, and applies it to the questions of...