Using textual analysis and comparing cybersecurity-risk disclosures of firms that were hacked to others that were not, we propose a novel firm-level measure of cybersecurity risk for all US-listed firms. We then examine whether cybersecurity risk is priced in the cross-section of stock returns....

We investigate the relationship between the extent of a city's subway network, its population and its spatial configuration. For the 632 largest cities in the world we construct panel data describing population, measures of centralization calculated from lights at night data, and the extent of...

New York City's multipronged subway system was a major disseminator – if not the principal transmission vehicle – of coronavirus infection during the initial takeoff of the massive epidemic that became evident throughout the city during March 2020. The near shutoff of subway ridership in...

We investigate the effect of subway system openings on urban air pollution. On average, particulate concentrations are unchanged by subway openings. For cities with higher initial pollution levels, subway openings reduce particulates by 4% in the area surrounding a city center. The effect decays...

Urban rail transit investments are expensive and irreversible. Since people differ with respect to their demand for trips, their value of time, and the types of real estate they live in, such projects are likely to offer heterogeneous benefits to residents of a city. Using the opening of a major...

This paper uses fare changes in Mexico City, Guadalajara, and Monterrey to estimate the price elasticity of demand for urban rail transit. In two of the cases there is a significant fare increase (30%+), and in the third there is a 60-day fare holiday. Ridership responds sharply in the expected...

This paper examines the importance of buyer-supplier relationships, geography and the structure of the production network in firm performance. We develop a simple model where firms can outsource tasks and search for suppliers in different locations. Low search and outsourcing costs lead firms to...

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...

Widely different approaches to rail reform are evident across countries and within Australia. Reforms have involved structural separation (both vertical and horizontal) and varying degrees of private sector involvement. Evidence from Australian experience suggests that no one size fits all. The...

How large are the benefits of transportation infrastructure projects, and what explains these benefits? To shed new light on these questions, this paper uses archival data from colonial India to investigate the impact of India's vast railroad network. Guided by four predictions from a general...