From 1991 to 2003, the fraction of Medicaid recipients enrolled in HMOs and other forms of Medicaid managed care (MMC) increased from 11 percent to 58 percent. This increase was largely driven by state and local mandates that required most Medicaid recipients to enroll in an MMC plan....

State governments contract with health maintenance organizations (HMOs) to coordinate medical care for nearly 20 million Medicaid recipients. Identifying the causal effect of HMO enrollment on government spending and health care quality is difficult if, as is often the case, recipients have the...

This paper examines the relationship between gun ownership and crime. Previous research has suffered from a lack of reliable data on gun ownership. I exploit a unique data set to reliably estimate annual gun ownership rates at both the state and the county level during the past two decades. My...

I exploit a plausibly exogenous change in hospital financial incentives to examine whether the behavior of private not-for-profit hospitals varies with the share of nearby hospitals organized as for-profit firms. My results show that not-for-profit hospitals in for-profit intensive areas are...

The hospital market is served by firms that are private for-profit, private not-for-profit, and government-owned and operated. I use a plausibly exogenous change in hospital financing that was intended to improve medical care for the poor to test three theories of organizational behavior. My...

The federal-state Medicaid program insures 43 million people for virtually all of the prescription drugs approved by the FDA. To determine the price that it will pay for a drug treatment, the government uses the average price in the private sector for that same drug. Assuming that Medicaid...

We study the relationship between market structure and public procurement outcomes. In particular, we ask whether and to what extent consolidation-driven increases in industry concentration affect the way in which the government procures its goods and services. We focus on the defense industry,...

There is considerable controversy over the use of private insurers to deliver public health insurance benefits. We investigate the efficiency consequences of patients enrolling in Medicare Advantage (MA), private managed care organizations that compete with the traditional fee-for-service...