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....

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...

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...

Although the theoretical literature on corruption is well developed, empirical work in this area has lagged because it has proven difficult to isolate corrupt behavior in the data. In this paper, we look for evidence of corruption in an unlikely place: the highest echelons of Japanese sumo...

The Affordable Care Act (ACA) authorized the largest expansion of public health insurance in the U.S. since the mid-1960s. We exploit ACA-induced changes in the discontinuity in coverage at age 65 using a regression discontinuity based design to examine effects of the expansion on health...

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,...