Projects

Causal Machine Learning

Combining techniques from causal inference, machine learning, and semiparametric statistics to develop efficient, robust estimators of treatment effects in experimental and observational study settings.

Causal Subgroup Discovery

Discovering population segments (subgroups) and evaluating the population-level effects of learned dynamic treatment policies using causal machine learning.

Nonparametric Sieve Estimation

Developing nonparametric estimators with novel properties using undersmoothing (sieve estimation) principles with semiparametric efficiency theory.

Causal Vaccine Efficacy Evaluation

Efficient estimation of the causal impacts of vaccine-induced immune responses in complex trials.

The Highly Adaptive Lasso Estimator

Efficient estimation of functional target parameters based on the highly adaptive lasso minimum loss estimator (HAL-MLE).

(Contrastive) Covariance Estimation

Cross-validated selection; robust, sparsified estimation; and dimension reduction for high-dimensional (contrastive) covariance matrices.

Biased Sampling Designs

Evaluating corrections for biased sampling designs, including two-phase (e.g., case-cohort) sampling and similar problems.

Nonparametric Causal Mediation Analysis

Defining novel, more flexible causal effects for mediation analysis, primarily using the formalism of stochastic interventions.

Causal Effects of Stochastic Interventions

Estimating the causal effects of stochastic treatment regimes, including conditional density estimation and two-phase sampling corrections.

Semiparametric Variance Moderation

Introducing empirical Bayes variance moderation for data adaptive variable importance in high-dimensional biology applications.