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Department of Statistics, The Ohio State University
Statistics and Biostatistics Colloquium Series
Variable selection in the linear regression model with censored
outcomes
Brent A. Johnson
University of North Carolina
3:30PM - Thursday, February 9, 2006
Room 170, Eighteenth Avenue Bldg. (EA 170)
ABSTRACT
Variable selection is an important topic in the statistical sciences with
applications in many disciplines including epidemiology, engineering, and
econometrics. Outcome censoring adds an additional layer of complication to
the variable selection procedures and improper handling of such data leads to
biased results and spurious conclusions. A biomedical application of
variable selection with censored data occurs in clinical trials with
staggered entry and subjects followed until the study endpoint or end of
follow-up, whichever comes first. We discuss two ideas for variable
selection: the first idea is a class of shrinkage estimators based on
penalizing a vector of estimating equations while the second defines an
objective stopping rule (through the addition of pseudo variables) which is
then used in a final forward selection algorithm. The proposed procedures
offer scientists and investigators semiparametric alternatives to methods
based on the partial likelihood. We explore the operating characteristics of
the proposed methods in small samples and illustrate their utility by
applying the methods to real data.
Meet the speaker in Room 212 Cockins Hall at 4:30
p.m. Refreshments will be served.
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