Many studies use shift-share (or “Bartik”) instruments, which average a set of shocks with
exposure share weights. We provide a new econometric framework for shift-share instrumental …

We develop new tools for estimating the causal effects of treatments or instruments that
combine multiple sources of variation according to a known formula. Examples include …

Charter takeovers are traditional public schools restarted as charter schools. We develop a
grandfathering instrument for takeover attendance that compares students at schools …

Conventional value-added models (VAMs) compare average test scores across schools after
regression-adjusting for students’ demographic characteristics and previous scores. This …

We recently reported two common filaggrin (FLG) null mutations that cause ichthyosis vulgaris
1 and predispose to eczema and secondary allergic diseases 2 . We show here that these …

BACKGROUND: IgE-mediated peanut allergy is a complex trait with strong heritability, but its
genetic basis is currently unknown. Loss-of-function mutations within the filaggrin gene are …

Atopic dermatitis (AD) is a common disease with a complex etiology in childhood and adult
life. A significant proportion of childhood AD is transient, but in many cases it persists into …

This investigation provides molecular analyses of the periodontal microbiota in health and
disease. Subgingival samples from 47 volunteers with healthy gingivae or clinically …

BACKGROUND:: Onychomycosis is observed less frequently in children than adults. Until
recently management of onychomycosis in children included topical formulations, oral …

Disparities by race, gender, and other protected characteristics have been widely documented
in many important settings—such as employment, housing, criminal justice, education, …