Nearly half of all transactions in the $5 trillion market for manufactured goods in the United States were intermediated by wholesalers in 2012, up from 32 percent in 1992. Seventy percent of this increase is due to the growth of "superstar" firms - the largest one percent of wholesalers....

We study whether Amazon engages in self-preferencing on its marketplace by favoring its own brands (e.g., Amazon Basics) in search. To address this question, we collect new micro-level consumer search data using a custom browser extension installed by a panel of study participants. Using this...

The growing discussions of impact investing and stakeholder capitalism have increased interest in measuring companies' social impact. We conceptualize corporate social impact as the welfare loss that would be caused by a firm's exit. To illustrate, we quantify the social impacts of 74 firms in...

While the traditional role of insurers is to provide protection against idiosyncratic risks of individuals, insurers themselves face substantial uncertainties due to aggregate shocks. To prevent insurers from passing through aggregate risks to consumers, governments have increasingly adopted...

This paper presents a new method for estimating discrete games based on bounds of conditional choice probabilities. The method does not require solving the game and is scalable to models with many firms and many discrete decisions. We apply the method to study merger effects on firm entry and...

Prices are regulated in many markets, ranging from healthcare to labor to telecommunications. This paper reinterprets the variables in the basic supply-demand model so that both product-definition and quantity are equilibrium outcomes. Specifically, compliance with price controls is achieved by...

This paper examines the regulation of technological innovation direction under uncertainty about potential harms. We develop a model with two competing technological paths and analyze various regulatory interventions. Our findings show that market forces tend to inefficiently concentrate...

This paper analyzes dynamic oligopoly models where investment is the principal strategic variable of interest, there are a large number of investment choices, and there are privately observed shocks to the marginal cost of investment. We show that simulation methods to compute these models can...

This paper studies how market competition influences the algorithmic design choices of firms in the context of targeting. Firms face the general trade-off between bias and variance when choosing the design of a supervised learning algorithm in terms of model complexity or the number of...

We study the causal interpretation of instrumental variables (IV) estimands of nonlinear, multivariate structural models with respect to rich forms of model misspecification. We focus on guaranteeing that the researcher's estimator is sharp zero consistent, meaning that the researcher concludes...