Dr. Ying Wei's research interests are in the general area of quantile regression, longitudinal data, and semi-parametric models, with a focus on developing methodologies of longitudinal growth chart construction. This screening process can provide an individual's current growth status by taking into account one's personal profiles. Dr. Wei's methodologies provide flexibility by avoiding underlying distribution assumption and accommodate unequally-spaced measurement time spacings. She also has investigated effective methods to make inferences, diagnose model goodness-of-fit, and assess uncertainty of screening based on the estimated models.