Accession Number : ADA322221

Title :   Statistical Methods for Analyzing Time-Dependent Events in Breast Cancer Chemprevention Studies.

Descriptive Note : Annual rept. 30 Sep 95-29 Sep 96,

Corporate Author : STRANG-CORNELL CANCER RESEARCH LAB NEW YORK NY

Personal Author(s) : Wong, George Y.

PDF Url : ADA322221

Report Date : OCT 1996

Pagination or Media Count : 13

Abstract : The overall aim of our research proposal is the statistical inference of nonparametric estimates, the redistribution-to-the-inside estimator (RTIE) and the generalized maximum likelihood estimator (GMLE), for the survival function, where the survival time is subject to interval censoring. The GMLE is the standard optimal procedure in survival analysis. However, a closed form expression for this estimator has not been derived, and the asymptotic distribution theory for it has been very little known. In our original proposal, we created the RTIE, which has a closed form expression, and which has been shown by us to be the GMLE under certain conditions. Working on the theory of the RTIE has provided us with important clues to the asymptotic theory concerning tile GMLE. Our research efforts in the second year have focused on attacking the asymptotic distribution of the GMLE under the assumption that the censoring random vector is discrete. Under such an assumption, we have successfully established the asymptotic properties of the GMLE as well as those of the RTIE.

Descriptors :   *TIME DEPENDENCE, *STATISTICAL INFERENCE, *BREAST CANCER, TIME INTERVALS, SURVIVABILITY, CHEMICALS, MAXIMUM LIKELIHOOD ESTIMATION, STATISTICAL ANALYSIS, STANDARD DEVIATION, ASYMPTOTIC NORMALITY, PREVENTIVE MEDICINE, CENSORSHIP.

Subject Categories : Numerical Mathematics
      Statistics and Probability
      Operations Research
      Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE