We provide new theory and evidence on the role of consumption access in understanding the agglomeration of economic activity. We combine smartphone data that records user location every 5 minutes of the day with economic census data on the location of service-sector establishments to measure...

For much of 2020, the COVID-19 epidemic upended social and economic life globally. In an effort to reduce COVID-19 risks in the U.S., state and local governments issued many recommendations and regulations to induce social distancing, adding to voluntary reductions in interpersonal contact. The...

This paper examines a model in which advertisers bid for "sponsored-link" positions on a search engine. The value advertisers derive from each position is endogenized as coming from sales to a population of consumers who make rational inferences about firm qualities and search optimally....

Search frictions can explain why the "law of one price" fails in retail markets and why even firms selling commodity products have pricing power. In online commerce, physical search costs are low, yet price dispersion is common. We use browsing data from eBay to estimate a model of consumer...

The financial motivation to earn advertising revenue by spreading misinformation has been widely conjectured to be among the main reasons misinformation continues to be prevalent online. Research aimed at reducing the spread of misinformation has so far focused on user-level interventions with...

Despite substantial efforts to help consumers search in more intuitive ways, text search remains the predominant tool for product discovery online. In this paper, we explore the effects of visual and textual cues for search refinement on consumer search and purchasing behavior. We collaborate...

Research on the causal effects of online advertising on consumer welfare is limited due to challenges in running large-scale field experiments and tracking effects over extended periods. We analyze a long-running field experiment of online advertising in which a random 0.5% subset of all users...

We conducted a randomized controlled trial testing the effect of modest incentives to attend the gym among new members of a fitness facility, a population that is already engaged in trying to change a health behavior. Our experiment randomized 836 new members of a private gym into a control...

We present results from a nationally representative survey of American adults, guided by a simple theoretical model expressing health care-seeking behavior as a function of economic and behavioral fundamentals and highlighting the role of trust. We report several findings. First, we document a...

Subsidies to consumers may cause firms to charge higher prices, which offsets consumer benefits from subsidies. We study a subsidy program design that mitigates such price increases by making products' eligibility for a subsidy dependent on firms' commitment to price ceilings. To quantify the...