title: Survival impact index and ultrahigh-dimensional model-free screening with survival outcomes.
abstract: Motivated by ultrahigh-dimensional biomarkers screening studies, we propose a model-free screening approach tailored to censored lifetime outcomes. Our proposal is built upon the introduction of a new measure, survival impact index (SII). By its design, SII sensibly captures the overall influence of a covariate on the outcome distribution, and can be estimated with familiar nonparametric procedures that do not require smoothing and are readily adaptable to handle lifetime outcomes under various censoring and truncation mechanisms. We provide large sample distributional results that facilitate the inference on SII in classical multivariate settings. More importantly, we investigate SII as an effective screener for ultrahigh-dimensional data, not relying on rigid regression model assumptions for real applications. We establish the sure screening property of the proposed SII-based screener. Extensive numerical studies are carried out to assess the performance of our method compared with other existing screening methods. A lung cancer microarray data is analyzed to demonstrate the practical utility of our proposals.
authors.affiliation: Department of Statistics and Applied Probability, National University of Singapore, Singapore 117546, Singapore.|Duke-NUS Graduate Medical School, Singapore.|Singapore Eye Research Institute, Singapore.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40202.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: Department of Biostatistics and Bioinformatics, Emory University, Atlanta, Georgia, 30321, U.S.A.
authors.forename: Limin
authors.initials: L
authors.lastname: Peng
authors.affiliation: Department of Statistics and Applied Probability, National University of Singapore, Singapore 117546, Singapore.|Singapore Eye Research Institute, Singapore.|McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, Texas 75390, U.S.A.
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Huang
mesh_terms: D015415:Biomarkers; D001699:Biometry / Q000379:methods*; D003198:Computer Simulation; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality*; D046228:Microarray Analysis; D015233:Models, Statistical; D018709:Statistics, Nonparametric; D016019:Survival Analysis
chemical_list: D015415:Biomarkers
keywords: Empirical process; Gene expression; Model-free screening; Sure independence screening; Survival distribution