The distribution of the population of cities has attracted a great deal of attention, in part because it sharply constrains models of local growth. However, to this day, there is no consensus on the distribution below the very upper tail, because available data need to rely on the "legal" rather...

We find that a firm's investment is highly sensitive to the investments of other firms headquartered nearby, even those in very different industries. It also responds to fluctuations in the cash flows and stock prices (q) of local firms outside its sector. These patterns do not appear to reflect...

We find that a firm's tendency to engage in financial misconduct increases with the misconduct rates of neighboring firms. This appears to be caused by peer effects, rather than exogenous shocks like regional variation in enforcement. Effects are stronger among firms of comparable size, and...

This paper develops a model of the geographic distribution of crime in an urban area. When the police protect some neighborhoods (concentrated protection), the city becomes segregated. When the police are evenly deployed across the city (dispersed protection), an integrated city emerges. Unequal...

We study the tendency to connect to the Internet, and the online and offline shopping behavior of connected persons, to draw inferences about whether the Internet is a substitute or a complement for cities. We document that larger markets have more locally-targeted online content and that...

Most economic activity occurs in cities. This creates a tension between local increasing returns, implied by the existence of cities, and aggregate constant returns, implied by balanced growth. To address this tension, we develop a theory of economic growth in an urban environment. We show that...

What impact will terrorism have on America's cities? Historically, large-scale violence has impacted cities in three ways. First, concentrations of people have an advantage in defending themselves from attackers, making cities more appealing in times of violence. Second, cities often make...

One of the most important representations of an urban spatial structure is its density. Indeed, an urban area is defined as a densely populated place with a sizeable number of inhabitants. Yet, despite the fact that the defining element of an urban area is its density, few scholars have...

Comprehensive zoning is ubiquitous in U.S. cities, yet we know surprisingly little about its long-run impacts. We provide the first attempt to measure the causal effect of land use regulation over the long term, using as our setting Chicago's first (1923) comprehensive zoning ordinance. Our...

We document several empirical regularities regarding the evolution of urban structure in the largest U.S. metropolitan areas over the period 1980-1990. These regularities relate to changes in resident population, employment, occupations, as well as the number and size of establishments in...