1 citations · 2 across the 6 of their papers we have counts for
4 papers · 1 filter
Recanting twins: addressing intermediate confounding in mediation analysis
Tat-Thang Vo, Nicholas Williams, Richard Liu +2
The presence of intermediate confounders, also called recanting witnesses, is a fundamental challenge to the investigation of causal mechanisms in mediation analysis, preventing th…
Two-Step Targeted Minimum-Loss Based Estimation for Non-Negative Two-Part Outcomes
Nicholas T. Williams, Richard Liu, Katherine L. Hoffman +3
Non-negative two-part outcomes are defined as outcomes with a density function that have a zero point mass but are otherwise positive. Examples, such as healthcare expenditure and…
Efficient and flexible causal mediation with time-varying mediators, treatments, and confounders
Iván Díaz, Nicholas Williams, Kara E. Rudolph
Interventional effects have been proposed as a solution to the unidentifiability of natural (in)direct effects under mediator-outcome confounders affected by the exposure. Such con…
Causal mediation with instrumental variables
Kara E. Rudolph, Nicholas Williams, Ivan Diaz
Mediation analysis is a strategy for understanding the mechanisms by which treatments or interventions affect later outcomes. Mediation analysis is frequently applied in randomized…