STATISTICS COLLOQUIUM
Thursday, April 5th, 2012 at 1.10pm, MSB 1143 (Seminar
Room)
Refreshments prior to seminar in MSB 4110 (Statistics Lounge)
Speaker:
Hongwei Zhao, ScD
Dept of Epidemiology &
Biostatistics, Texas A&M Health Science Center
Title: Generalized redistribute-to-the-right
algorithm: application to the analysis of censored cost data
Abstract: Costs
assessment and cost-effectiveness analysis serve as an essential part in economic
evaluation of medical interventions. In clinical trials and many observational
studies, costs as well as survival data are frequently censored. Standard
techniques for survival-type data are often invalid in analyzing censored cost
data, due to the induced dependent censoring problem (Lin et al., 1997). In
this talk, we will first examine the equivalency between a redistribute-to-the
right (RR) algorithm and the popular Kaplan-Meier method for estimating the
survival function of time (Efron, 1967). Next, we will extend the RR algorithm
to the problem of estimating mean costs with censored data, and propose a
simple RR (Pfeifer and Bang, 2005) and an efficient RR estimator. We will
establish the equivalency between the RR estimators and some existing cost
estimators derived from the inverse-probability-weighting technique and
semiparametric efficiency theory. Finally, we will extend the RR algorithm to
the problem of estimating the survival function of health costs, and conduct
simulation studies to compare a new RR survival estimator with some existing
survival estimators for costs.
