The COVID-19 pandemic exogenously hit many economies early 2020. Exploiting treatment heterogeneity, we use a conditional difference-in-differences design to causally identify how COVID-19 impacted firms'…
We show that in school systems with grade retention or redshirting birth cohort size is negatively related to the grade-level share of students who are too old for their grade. This compositional effect gives…
Technological advances have paved the way for urban air mobility (UAM) as a new mode of transportation, providing solutions for both inner-city and regional transportation. Novel vertical take-off and landing…