Measurement of seat belt and air bag effectiveness is complicated by the fact that systematic data are collected only for crashes in which a fatality occurs. These data suffer from sample selection since seat belt and air bag usage influences survival rates which in turn determine whether a...

This paper uses a Ceridian transaction-by-transaction data set on purchases of diesel fuel by over-the-road truckers to form a monthly diesel volume purchase index from 1999 to 2011, purged of weekday, holiday and calendar effects. These high-frequency data support a new and improved set of...

We consider large, permanent shocks to individual occupations whose arrival date is uncertain. We are motivated by the advent of self-driving trucks, which will dramatically reduce demand for truck drivers. Using a bare-bones overlapping generations model, we examine an occupation facing...

This paper documents three new stylized facts showing that truckers in Colombia frequently choose to make complex chains of shipments in a single trip before returning home. It then provides a newmodel of optimal trucker trip-chaining with a general geography that is consistent with these facts

Young children are required to use child safety seats, and the age threshold at which children can legally graduate to seat belts has steadily increased. This paper tests the relative effectiveness of child safety seats, lap-and-shoulder seat belts, and lap belts in preventing injuries among...

Do investors anticipate that demands for racial equity will impact companies? We explore this question in the context of the Black Lives Matter (BLM) movement--the largest racially motivated protest movement in U.S. history--and its effect on the U.S. policing industry using a novel dataset on...

Given police abolitionism's new visibility after the 2020 racial justice protests, we assess stakeholder beliefs on the protests' stock impacts on police-affiliated firms. Experts generally underestimate the firms' stock gains, except situated experts like community organizers and police...

We document three facts about the global diffusion of surveillance AI technology, and in particular, the role played by China. First, China has a comparative advantage in this technology. It is substantially more likely to export surveillance AI than other countries, and particularly so as...

Road maintenance constitutes a significant component of public transportation spending at all levels of government. Formulation of efficient transportation infrastructure policy requires information about factors affecting road and traffic conditions. We generate the first causal evidence that...

Over 20 states have adopted laws requiring youths to wear a helmet when riding a bicycle. We confirm previous research indicating that these laws reduced fatalities and increased helmet use, but we also show that the laws significantly reduced youth bicycling. We find this result in standard...