Knowledge that Transforms

This paper studies the estimation and inference of time-varying impulse response functions in structural vector autoregressions (SVARs) identified with external instruments. Building on kernel estimators that allow for nonparametric time variation, we derive the asymptotic distributions of the relevant quantities. Our estimators are simple and computationally trivial and allow for potentially weak instruments. Simulations suggest satisfactory empirical coverage even in relatively small samples as long as the underlying parameter instabilities are sufficiently smooth. We illustrate the methods by studying the time-varying effects of global oil supply news shocks on US industrial production.

Healthcare providers often deviate from guidelines, leading to worse outcomes. I study the impact of academic detailing (also known as educational outreach) to primary care teams on safer pain management, risk evaluation, harm reduction, and opioid use disorder treatment. Using data from over 5 million patients, I find detailing improves provider behavior: it increases naloxone prescribing, prescription drug monitoring queries, and reduces opioid prescriptions for three years. Patients have fewer emergency visits and hospitalizations for overdoses, suicides, and accidents, especially heavy opioid users. Importantly, pain scores remain stable despite reduced opioid use, highlighting detailing's role in fostering safer, effective care.

This paper provides the first national analysis of how public scrutiny from high-profile police killings affect local policing and crime. These killings reduce arrests for low-level offenses without affecting arrests for serious crimes. They also result in a significant increase in serious offenses, particularly murders and robberies. The effects appear after communities become aware of the incident and are larger when media coverage is higher. The findings suggest that scrutiny drives the reductions in arrests, while the incidents themselves—not reduced police activity—prompt the increases in crime. To mitigate crime, localities should focus on reducing police use of force.

We use third-party reported data and two quasi-experiments from Norway to study how tax incentives affect charitable giving. First, using a shock to wealth tax exposure, we estimate the semi-elasticity of giving with respect to the after-tax return on wealth. Inconsistent with the notion that households accelerate giving to reduce future taxes, we find that a 1% wealth tax reduces giving by 26%. Second, using bunching at an income-tax deduction threshold, we estimate a moderate own-price elasticity of giving of -0.44. This elasticity exhibits little heterogeneity with respect to income and wealth but is considerably larger for religious giving.

I provide new evidence of the effects of income on child maltreatment. I exploit a discontinuity in child-related tax benefits, which results in otherwisesimilar families receiving considerably different refunds during the first year of a child's life. I use twenty years of linked administrative data from California to determine the effects of this additional income on child protection system (CPS) involvement. A one-time $1,000 transfer to low-income households decreases the number of referrals to CPS (3%) and number of days spent in foster care (7%) in the first 3 years of life. Effects persist through at least age 8.

Foster care placement is strongly associated with crime—for example, close to one fifth of the prison population in the U.S. is comprised of former foster children—yet there is little evidence on whether this relationship is causal. Leveraging the quasi-random assignment of investigators and administrative data from Michigan, we show that placement substantially reduced the chances of adult arrests, convictions, and incarceration for children at the margin. Exploring mechanisms, we find evidence that children’s birth parents made positive changes following placement. We show that most children in our setting reunified with their parents after being in foster care for one to two years, and that parents themselves were less likely to have criminal justice contact after placement. Considering recent historic federal policy which prioritizes keeping children with their families, our analysis indicates that safely reducing foster care caseloads will require improving efforts to ensure child wellbeing in the home.

This study re-examines Dube (2019), which finds large and statistically significant poverty-reducing effects of the minimum wage. We show that his estimated elasticities are fragile and sensitive to (1) time period under study, (2) choice of macroeconomic controls, (3) limiting counterfactuals to geographically proximate states (“close controls”), which poorly match treatment states' pre-treatment poverty trends, and (4) accounting for potential bias caused by heterogeneous and dynamic treatment effects. Using data spanning nearly four decades from the March Current Population Survey and a dynamic difference-in-differences (DiD) approach, we find that a 10 percent increase in the minimum wage is associated with a (statistically insignificant) 0.17 percent increase in the probability of longer-run poverty among all persons. With 95% confidence, we can rule out long-run poverty elasticities with respect to the minimum wage of less than -0.129. Our null results persist across a variety of DiD estimation strategies, including two-way fixed effects, stacked DiD, Callaway and Sant'Anna, and synthetic DiD. We conclude that, to date, the preponderance of evidence suggests that minimum wage increases are an ineffective policy strategy for alleviating poverty.

International transboundary air pollution poses a significant threat to the global economy and health, yet conventional economic analyses seldom incorporate this phenomenon. By integrating transboundary particle trajectory data with individual-level mortality and emergency department visit records, we find that air pollution from China significantly increases mortality and morbidity in South Korea. We evaluate the spillover benefits of recent Chinese environmental regulations and find that a country's environmental policies could generate substantial hidden benefits for neighboring countries. Finally, we demonstrate that China's potentially strategic reductions in pollution could have undermined these benefits, highlighting the implications for additional gains through Coasian bargaining.

We estimate the impacts of temperature on alleged and substantiated child maltreatment among young children using administrative data from state child protective services agencies. Leveraging short-term weather variation, we find increases in the number of young children involved in cases of alleged and substantiated maltreatment during hot periods. Additional analysis identifies neglect as the temperature-sensitive maltreatment type, and we find some evidence that adaptation via air conditioning mitigates this relationship. Given that climate change will increase exposure to extreme temperatures, our findings speak to additional costs of climate change among the most vulnerable.

This paper studies the effects of transitioning from a system of sales taxes to a value-added tax (VAT) on firm-level outcomes. We construct a dataset of product- and state-specific tax rates before and after India gradually switched from a sales tax to a VAT. Exploiting staggered state-level adoptions, we first show that following the transition, effective tax rates declined substantially and complexity as measured by various proxies generally also fell. We then show that sales increased by 57% in the medium run. The reform resulted in increased earnings for workers and higher amounts of capital and digital accounting.