Young children are required to use child safety seats, and the age threshold at which children can legally graduate to seat belts has steadily increased. This paper tests the relative effectiveness of child safety seats, lap-and-shoulder seat belts, and lap belts in preventing injuries among...

Endogenous patient sorting across hospitals can confound performance comparisons. This paper provides a new lens to compare hospital performance for emergency patients: plausibly exogenous variation in ambulance-company assignment. Ambulances are effectively randomly assigned to patients in the...

In response to unsustainable growth in health care spending, there is enormous interest in reforming the payment system to “pay for quality instead of quantity.” While quality measures are crucial to such reforms, they face major criticisms largely over the potential failure of risk...

Nearly 20% of young prison inmates spent part of their youth in foster care - the placement of abused or neglected children with substitute families. Little is known whether foster care placement reduces or increases the likelihood of criminal behavior. This paper uses the placement frequency of...

Patient sorting can confound estimates of the returns to physician human capital. This paper compares nearly 30,000 patients who were randomly assigned to clinical teams from one of two academic institutions. One institution is among the top medical schools in the country, while the other...

Some gasoline markets exhibit remarkable price cycles, where price spikes are followed by a string of small price declines until the next price spike. This pattern is predicted from a model of competition driven by Edgeworth cycles, as described by Maskin and Tirole. We extend the Maskin and...

Patients who receive more hospital treatment tend to have worse underlying health, confounding estimates of the returns to such care. This paper compares the costs and benefits of extending the length of hospital stay following delivery using a discontinuity in stay length for infants born close...

Health care spending varies widely across markets, yet there is little evidence that higher spending translates into better health outcomes, possibly due to endogeneity bias. The main innovation in this paper compares outcomes of patients who are exposed to different health care systems that...

There is widespread agreement that the US healthcare system wastes as much as 5% of GDP, yet little consensus on what care is actually unproductive. This partly arises because of the endogeneity of patient choice of treatment location. This paper uses the effective random assignment of patients...

Measuring physician quality is fundamental to understanding healthcare productivity, yet patient sorting can confound attempts to estimate the types of physicians that improve survival. This paper aims to overcome selection bias by exploiting plausibly exogenous variation in the mix of...