A Simulation Study of Estimators in Stratified Proportional Hazards Models
نویسنده
چکیده
It is common for large population-based surveys to select a sample from a population using a complex design. A simulation study was conducted to compare the estimates from the stratified proportional hazards model with the weighted estimates of the Binder method, when a stratified random sample of the population is used. The SAS PHREG procedure performs regression analysis of survival data based on the proportional hazards model while the SUDAAN SURVIVAL procedure estimates the parameters using the Binder method. Both procedures were used in this study to give estimates of regression parameters based on the two different methods of interest. This study shows that the estimates form the stratified proportional hazard model perform well under the assumptions for stratified proportional hazard models. The estimates from the Binder method show a tendency to underestimate the true value and gave the estimates from the unstratified finite population.
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