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 rates of gun ownership at both the state and the county levels during the past two decades. My findings demonstrate that changes in gun ownership are significantly positively related to changes in the hom-icide rate, with this relationship driven almost entirely by an impact of gun ownership on murders in which a gun is used. The effect of gun ownership on all other crime categories is much less marked. Recent reductions in the fraction of households owning a gun can explain one-third of the differential decline in gun homicides relative to nongun homicides since 1993. I.

In 2003 the federal-state Medicaid program provided prescription drug coverage to more than 50 million people. To determine the price that it will pay for each drug, Medicaid uses the average private sector price. When Medicaid is a large part of the demand for a drug, this creates an incentive for its maker to increase prices for other health care consumers. Using drug utilization and expenditure data for the top 200 drugs in 1997 and in 2002, we investigate the relationship between the Medicaid market share (MMS) and the average price of a prescription. Our estimates imply that a 10-percentage-point increase in the MMS is associated with a 7 to 10 percent increase in the average price of a prescription. In addition, the Medicaid rules increase a firm's incentive to introduce new versions of a drug in order to raise price. We find empirical evidence that firms producing newer drugs with larger sales to Medicaid are more likely to introduce new versions. Taken together, our findings suggest that government procurement rules can alter equilibrium price and product proliferation in the private sector.

Medicare Part D began coverage of prescription drugs in 2006. Rather than setting pharmaceutical prices, the government contracted with private insurers to provide drug coverage. Theory suggests that additional insured consumers will raise the optimal price of a branded drug, while the insurer's ability to move demand to substitute treatments may lower prices. We estimate the program's effect on the price and utilization of pharmaceutical treatments. We find that Part D enrollees paid substantially lower prices than while uninsured, and increased their utilization of prescription drugs. We find relative price declines only for drugs with significant therapeutic competition.

Although theory on corruption is well developed, it has proven difficult to isolate corrupt behavior empirically. In this paper, we provide overwhelming statistical evidence documenting match rigging in Japanese sumo wrestling. A non-linearity in the incentive structure of promotion leads to gains from trade between wrestlers on the margin for achieving a winning record and their opponents. We show that wrestlers win a disproportionate share of the matches when they are on the margin. Collusion, rather than increased effort, appears to explain the results. Wrestlers who are victorious when needing a victory lose more often than would be expected the next time they meet that same opponent, suggesting that part of the payment for throwing a match is future payment in kind. Cheating disappears in times of high media scrutiny. In addition to collusion by individual wrestlers, there is also evidence of reciprocity agreements across stables of wrestlers, suggesting a centralized element to the match rigging.

We examine whether and to what extent consolidation in the US health insurance industry has contributed to higher employer-sponsored insurance premiums. We exploit the differential impact across local markets of a national merger of two insurers to identify the causal effect of concentration on premiums. Using data for large groups, we estimate premiums in average markets were approximately seven percentage points higher by 2007 due to increases in local concentration from 1998–2006. We also find evidence consolidation facilitates the exercise of monopsonistic power vis-à-vis physicians, leading to reductions in their absolute employment and earnings relative to other healthcare workers. JEL: G22, I13

Medicare Part D began coverage of prescription drugs in 2006. Using data from the first year of the program we found that Part D reduced pharmaceutical prices for Medicare recipients, with these effects driven by enrollees previously without drug coverage. In this paper we extend our analysis through 2009, the fourth year of the program, to investigate whether plans continued to extract price concessions in return for favorable formulary placement, or if consumer inertia or other factors caused prices to bounce back after their initial decline. We find price declines persisted through at least the third year of the program.

A set of studies conducted over the last 15 years has produced a near consensus that the Social Security Disability Insurance system (SSDI) has substantial disincentive effects on the labor supply of near elderly males, diminishing labor force participation, increasing the sensitivity of labor force exit decisions to adverse economic shocks, and encouraging those nearing retirement to claim disability benefits and subsequently transfer into the Social Security retirement program. Yet, efforts by the Social Security Administration (SSA) to encourage labor supply among the disabled by removing the work disincentives built into SSDI have been almost entirely unsuccessful. Most notably, in 1999, Congress authorized the Ticket to Work program, which provides an array of inducements for current SSDI beneficiaries to take up employment, including permitting a trial work period of up to nine months, providing 7.75 years of ongoing Medicare eligibility following return to work, and providing three years of automatic benefit reinstatement when claimants’ workplace earnings fall below a threshold level. Each of these steps reduces the implicit tax placed on labor supply by the SSDI program. Despite these lures, fewer than 1,400 (0.01 percent) of the 12.2 million tickets issued to date have led to successful workforce integration (Autor and Duggan 2006).

We study Medicare’s competitive bidding program for durable medical equipment. We use Medicare claims data to examine the effect on prices and utilization, focusing on continuous positive airway pressure devices for sleep apnea. We find that spending falls by 47.2% after a highly imperfect bidding mechanism is introduced. This is almost entirely driven by a 44.8% price reduction, though quantities also fall by 4.3%. To disentangle supply and demand, we leverage differential cost sharing across Medicare recipients. We measure a demand elasticity of -0.272 and find that quantity reductions are concentrated among less clinically appropriate groups.

Under the Affordable Care Act, individual states have discretion in how they define coverage regions, within which insurers must charge the same premium to buyers of the same age, family structure, and smoking status. We exploit variation in these definitions to investigate whether the size of the coverage region affects outcomes in the ACA marketplaces. We find large consequences for small and rural markets. When states combine small counties with neighboring urban areas into a single region, the included rural markets see 0.6 to 0.8 more active insurers, on average, and savings in annual premiums of between $200 and $300.