Using data on 4.1 million apps at the Google Play Store from 2016 to 2019, we document that GDPR induced the exit of about a third of available apps; and in the quarters following implementation, entry of new apps fell by half. We estimate a structural model of demand and entry in the app...

Artificial Intelligence is a powerful new technology that will likely have large impacts on the size, direction and composition of international trade flows. Yet almost nothing is known empirically about this. One AI-enabled set of services that can be tracked resides in the palm of our hands:...

The rise of artificial intelligence (AI) and of cross-border restrictions on data flows has created a host of new questions and related policy dilemmas. This paper addresses two questions: How is digital service trade shaped by (1) AI algorithms and (2) by the interplay between AI algorithms and...

This paper develops a dynamic model of technology adoption featuring strategic complementarities: the benefits of usage increase with the number of adopters. We study the diffusion of new means of payments, where such complementarities are pervasive. We show that complementarities give rise to...

Mobile app commissions paid by app developers to a monopolist device maker/app store operator are examined. Three results are demonstrated. First, unregulated app commissions are set at a level that maximises consumer surplus. Second, eliminating app commissions will lead to higher device...

We examine the role of state and local policies to encourage social distancing, including stay at home orders, public school closures, and restrictions on restaurants, entertainment, and large social gatherings. Outcomes come from cell phone records and include foot traffic in six industries...

Market definition is essential to merger analysis. Because no standard approach to market definition exists, opposing parties in antitrust cases often disagree about the extent of the market. These differences have been particularly relevant in the hospital industry, where the courts have denied...

Amenities such as good food, attentive staff, and pleasant surroundings may play an important role in hospital demand. We use a marketing survey to measure amenities at hospitals in greater Los Angeles and analyze the choice behavior of Medicare pneumonia patients in this market. We find that...

When a product's product provision entails fixed costs, it will be made available only if a sufficient number of people want it. Some products are produced and consumed locally, so that provision requires not only a large group favoring the product but a large number nearby. Just as one has an...

The hospital industry is one of the most important industries in the U.S., and industry structure can have profound effects on the functioning of markets. Using county-level panel data, we study the effect of public subsidies from the Hospital Survey and Construction Act of 1946, known as the...