Method Development for Censored Quantile Regression

Emory University, Atlanta GA

Investigators

Abstract

Quantile regression has shown great promise in censored data analysis. The investigator proposes to broaden the scope of censored quantile regression by developing methods that can accommodate practical situations where censoring mechanism is more complicated than univariate random censoring. Part of research goals for the 3-year plan are: (1) to develop quantile regression methods in the presence of dependent censoring which can provide semiparametric sensitivity analysis of regression quantiles or joint inference on conditional quantiles of the response and response?censoring dependency; (2) to derive a new formulation of doubly censored regression quantiles based on a stochastic integral equation and provide practical remedies for addressing the associated identifiability issues; (3) to develop publicly available software which implements the proposed cutting-edge statistical methodology. The investigator plans to provide rigorous asymptotic studies for the proposed methods utilizing theory in empirical processes, stochastic integral equation, and functional analysis, and other statistical and probabilistic techniques. The proposed research will have significant impact and many applications in diverse fields including biomedical research, economics, and public health studies. For example, the methods to be developed can appropriately address the problem of nonrandom patient dropout in clinical studies, or account for the occurrence of event before study entry as well as no observation of event by the end of follow-up in many registry studies of chronic disease, thereby contributing to improving disease treatment or prevention. The investigator plans to integrate the results from the proposed research with education through student mentoring and course teaching, which may involve undergraduate students, and to widely disseminate the proposed research via publications, conference presentations, seminars, Internet postings, and free software.