A Second Order Semiparametric Method for Survival Analysis, with Application to an AIDS Clinical Trial Study
نویسندگان
چکیده
Motivated from a recent AIDS clinical trial study A5175, we propose a semiparametric framework to describe time to event data, where only the dependence of the mean and variance of the time on the covariates are specified through a restricted moment model. We use a second-order semiparametric efficient score combined with a nonparametric imputation device for estimation. Compared with an imputed weighted least square method, the proposed approach improves the efficiency of the parameter estimation whenever the third moment of the error distribution is nonzero. We compare the method with a parametric survival regression method in the A5175 study data analysis. In the data analysis, the proposed method shows better fit to the data with smaller mean squared residuals. In summary, this work provides a semiparametric framework in modeling and estimation of the survival data. The framework has wide applications in data analysis.
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