We consider the effect of abortion legalization on births in the United States. A simple theoretical model demonstrates that the impact of abortion legalization on the birth rate is ambiguous, because both pregnancy and abortion decisions could be affected. We use variation in the timing of...

This paper investigates the precision of conventional and unconventional estimates of the natural rate of unemployment (the 'NAIRU'). The main finding is that the NAIRU is imprecisely estimated: a typical 95% confidence interval for the NAIRU in 1990 is 5.1% to 7.7%. This imprecision obtains...

This paper develops asymptotic distribution theory for instrumental variable regression when the partial correlation between the instruments and a single included endogenous variable is weak, here modeled as local to zero. Asymptotic representations are provided for various instrumental variable...

Since 1990, U.S. policymakers have worked to close gaps in academic achievement by income and race (e.g. with school finance reform and school accountability systems) even as rising income inequality and income-based residential segregation have threatened to widen them. Using estimates of the...

We analyze admissions and transcript records for students at multiple Ivy-Plus colleges to study the relationship between standardized (SAT/ACT) test scores, high school GPA, and first-year college grades. Standardized test scores predict academic outcomes with a normalized slope four times...

In the three decades before the pandemic, mean achievement of U.S. 8th graders in math rose by more than half a standard deviation on the National Assessment of Educational Progress (NAEP). Between 2019 and 2022, U.S. students had forfeited 40 percent of that rise. To anticipate the consequences...

We measure the effect of district use of federal pandemic relief during the 2022-23 school year for a sample of more than 5000 districts in 29 states. We rely on several plausibly exogenous sources of variation in federal grants: differences in state Title I funding formulas, estimation error in...

Using testing data from 2.1 million students in 10,000 schools in 49 states (plus D.C.), we investigate the role of remote and hybrid instruction in widening gaps in achievement by race and school poverty. We find that remote instruction was a primary driver of widening achievement gaps. Math...

Hospitals play a key role in patient outcomes and spending, but efforts to improve their quality are hindered because we do not know whether hospital quality indicators are causal or biased. We evaluate the validity of commonly used quality indicators, such as mortality, readmissions, inpatient...

The evidence that productivity varies greatly across teachers has given rise to the idea that student achievement data should be included in performance evaluation, despite limited empirical evidence on subjective evaluation or the use of objective performance measures in U.S. public schools. In...