In many health domains, we are concerned that observed links - for example, between "healthy" behaviors and good outcomes - are driven by selection into behavior. This paper considers the additional factor that these selection patterns may vary over time. When a particular health behavior...

I generate new data on HIV incidence and prevalence in Africa based on inference from mortality rates. I use these data to relate economic activity (specifically, exports) to new HIV infections in Africa and argue there is a significant and large positive relationship between the two: a doubling...

The response of sexual behavior to HIV in Africa is an important input to predicting the path of the epidemic and to focusing prevention efforts. Existing estimates suggest limited behavioral response, but fail to take into account possible differences across individuals. A simple model of...

Childhood vaccinations are an important input to disease prevention, but vaccination rates have declined over the last decade due largely to parental fears about vaccine dangers. Education campaigns on the safety of vaccines seem to have little impact. Anecdotal evidence on disease outbreaks...

Individuals with obesity often appear reluctant to undertake dietary changes. Evaluating the reasons for this reluctance, as well as appropriate policy responses, is hampered by a lack of data on behavioral response to dietary advice. I use household scanner data to estimate food purchase...

A common heuristic for evaluating robustness of results to omitted variable bias is to look at coefficient movements after inclusion of controls. This heuristic is informative only if selection on observables is proportional to selection on unobservables. I formalize this link, drawing on theory...

We estimate the impact of district-level schooling mode (in-person versus hybrid or distance learning) on test scores. We combine Spring 2021 state standardized test score data with comprehensive data on schooling in the 2020-21 school year across 12 states. We find that pass rates declined...

We use grocery purchase data to analyze dietary changes. We show that households - including those with more income or education - do not improve diet in response to disease diagnosis or changes in household circumstances. We then identify households who show large improvements in diet quality....

Cellular technologies have become increasingly important in the developing world; infrastructure for mobile networks has expanded dramatically over the past two decades giving access to remote areas without previous phone service. Despite this expansion, relatively little is known about the...

Over the last two decades in India there have been large increases in outsourced jobs and large increases in schooling rates, particularly in English. Existing evidence suggests the trends are broadly related. In this paper we explore how localized these impacts are; this has implications for...