In my job market paper, I analyze the effects of changes in day-to-day air pollution levels on daily absences for New York City schools from 2006 to 2019. I combine EPA air quality data with absences for more than 1600 schools. To alleviate endogeneity concerns I use wind as an instrument for transport of air pollution. I estimate that an additional 1 $\mu$g/$m^3$ of PM2.5 pollution increases absences across all schools by 0.044%, and an extra part-per-billion (PPB) of Ozone increases it by 0.029%. PM2.5 pollution has the largest effects on elementary and middle schools, and on schools with more impoverished students. Examining trends across 14 years of pollution and absences, my results suggest that the decrease in average daily PM2.5 pollution of 5 $\mu$g/$m^3$ from 2006 to 2019 led to at least 0.2% fewer absences across NYC schools every day. In contrast, Ozone concentrations did not decline over time, and I find that Ozone affects high school absences more than it affects elementary or middle school absences. This work shows the improvements over time in air quality in New York City but also highlights the disparate impacts of air pollution.

Prescription Drug Monitoring Programs (PDMPs) seek to potentially reduce opioid misuse by restricting the sale of opioids in a state. We examine discontinuities along state borders, where one side may have a PDMP and the other side may not. We find that electronic PDMP implementation, whereby doctors and pharmacists can observe a patient’s opioid purchase history, reduces a state’s opioid sales but increases opioid sales in neighboring counties on the other side of the state border. We also find systematic differences in opioid sales and mortality between border counties and interior counties. These differences decrease when neighboring states both have ePDMPs, which is consistent with the hypothesis that individuals cross state lines to purchase opioids. Our work highlights the importance of understanding the opioid market as connected across counties or states, as we show that states are affected by the opioid policies of their neighbors.