Rates of COVID deaths and cases differ markedly across U.S. states, as do rates of vaccination. This study uses cross-state regressions to assess impacts of vaccinations on COVID outcomes. A number of familiar issues concerning cross-sectional regressions arise, including omitted variables,...

A key issue for the ongoing COVID-19 pandemic is whether non-pharmaceutical public-health interventions (NPIs) retard death rates. Good information about these effects comes from flu-related excess deaths in large U.S. cities during the second wave of the Great Influenza Pandemic, September...