I am Professor at the Department of Statistical Science with a secondary appointment at the Department of Biostatistics and Bioinformatics, Duke University. My main research interest is causal inference and its applications to health studies (also known as comparative effectiveness research) and computational social science. I also work on the interface between causal inference and machine learning. I have developed methods for propensity score, clinical trials, randomized experiments (e.g. A/B testing), difference-in-differences, regression discontinuity designs, representation learning. I also work on Bayesian analysis and statistical methods for missing data. I am serving as the editor for social science, biostatistics and policy for the journal Annals of Applied Statistics.