1,802 research outputs found
Survivor-complier effects in the presence of selection on treatment, with application to a study of prompt ICU admission
Pre-treatment selection or censoring (`selection on treatment') can occur
when two treatment levels are compared ignoring the third option of neither
treatment, in `censoring by death' settings where treatment is only defined for
those who survive long enough to receive it, or in general in studies where the
treatment is only defined for a subset of the population. Unfortunately, the
standard instrumental variable (IV) estimand is not defined in the presence of
such selection, so we consider estimating a new survivor-complier causal
effect. Although this effect is generally not identified under standard IV
assumptions, it is possible to construct sharp bounds. We derive these bounds
and give a corresponding data-driven sensitivity analysis, along with
nonparametric yet efficient estimation methods. Importantly, our approach
allows for high-dimensional confounding adjustment, and valid inference even
after employing machine learning. Incorporating covariates can tighten bounds
dramatically, especially when they are strong predictors of the selection
process. We apply the methods in a UK cohort study of critical care patients to
examine the mortality effects of prompt admission to the intensive care unit,
using ICU bed availability as an instrument
Review of Universities and Copyright Collecting Societies
Book review of DK Mendis, Universities and Copyright Collecting Societies
Don't Forget Non-Code Statutes
Laws that are not codified in statutory codes present special research challenges. Strategies, including checking compiler's notes and session laws, can help ensure all relevant laws are found
A Primer on Digital Object Identifiers for Law Librarians
Digital object identifiers have not received much attention by law librarians, but they may become more useful in the near future. This paper explains digital object identifiers and discusses how they are relevant to law librarians
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