We match cell phone data to administrative school records and combine it with information on school learning modes to study effective in-person learning (EIPL) in the U.S. during the pandemic. We find large differences in EIPL for the 2020-21 school year. Public schools averaged less EIPL than...

An important issue in the analysis of cross-sectional dependence which has received renewed interest in the past few years is the need for a better understanding of the extent and nature of such cross dependencies. In this paper we focus on measures of cross-sectional dependence and how such...