Publication Date: July 2020
Tracking human activity in real time and at ﬁne spatial scale is particularly valuable during episodes such as the COVID-19 pandemic. In this paper, we discuss the suitability of smartphone data for quantifying movement and social contact. We show that these data cover broad sections of the US population and exhibit movement patterns similar to conventional survey data. We develop and make publicly available a location exposure index that summarizes county-to-county movements and a device exposure index that quantiﬁes social contact within venues. We use these indices to document how pandemic-induced reductions in activity vary across people and places.
JEL Classification Codes: C8, R1, R4