| Summary: | 碩士 === 淡江大學 === 數學學系 === 85 === The purpose of this thesis is computer simulation,under the
acceleratedfailure time model(AFTM),to compare the power
performance of the rankestimating equation(REE,Chen and
Hsieh,1997) with that of the linear rankstatistic(LRS) of
Prentice(1978) in the survival time of two-group treatmentwith
right-censored data. The REE applies the Gehan''s(1965)
generalized Wilcoxon score,while theLRS is applicable with both
Wilcoxon and log-rank score.Without covariates,it is known that
the log-rank score will have bigger power than the Wilcoxonscore
when the hazard rates of two groups are parallel,and the
situationis reversed when this assumption is violated.Here we
consider the presenceof a concomitant covariable as well. The
main result simulation results are as follows:(1)All the powers
increases with the sample size,and decreases with the censored
percentage.(2)The Prentice''s LRS can not detect the presence of
a covariable,thus is affected in power performences.(3)When
the censored percentage is none or small,the REE is much better
than the LRS for alll cases studies,but the power of the REE
deteriorates as the percentage increases,which needs further
investigation.
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