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. These data cover broad sections of the US population...

Official price indexes, such as the CPI, are imperfect indicators of inflation calculated using ad hoc price formulae different from the theoretically well-founded inflation indexes favored by economists. This paper provides the first estimate of how accurately the CPI informs us about "true"...

A key reason for the existence of cities are the externalities created when people cluster together in close proximity. During Covid, such interactions came with health risks and people found other ways to interact. We document how cities changed during Covid and consider how the persistence of...

We study how preferences over the demographic composition of co-patrons affects income segregation in shared spaces. To distinguish demographic preferences from tastes for other venue attributes, we study venue choices within business chains. We find two notable regularities: preferences for...

A common tactic to estimate willingness-to-travel exploits variation in the relative proximity of consumers to supplier locations. The validity of these estimates relies on the exogeneity of that consumer-supplier distance. We argue that distance to suppliers is endogenous because suppliers...

"The agglomeration force behind the New Economic Geography literature initiated by Krugman is based on the notion that larger markets should have a lower variety adjusted price index. Despite his Nobel Prize, there have been no tests of this idea. This paper represents the first such test. Using...