On Wed, 7 Sep 2005, Basile Chaix wrote: > Dear all, > I would have some questions on the coxph function for survival analysis, > which I use with frailty terms. > > My model is: > mdcox<-coxph(Surv(time,censor)~ gender + age + frailty(area, dist='gauss'), > data) > I have a very large proportion of censored observations. > > - If I understand correctly, the function mdcox$frail will return the random > effect estimated for each group on the scale of the linear predictor?
Yes > - Similarly, the variance of the frailties is the variance of the terms on > the scale of the linear predictor? Yes > - A p-value is provided for this variance. Is that possible to obtain a 95% > CI for the variance of the random effect instead of a p-value? I don't think anyone knows how to do this. Personally, I'm not really convinced of the usefulness of these frailty models and I don't know how well their properties are known. I wouldn't use them except when I was actually interested in the variance components, and I haven't worked on any problems like that, so I haven't investigated the issue. [I don't write the survival package, I just port it] -thomas Thomas Lumley Assoc. Professor, Biostatistics [EMAIL PROTECTED] University of Washington, Seattle ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html