On Fri, Mar 9, 2012 at 3:08 AM, Terry Therneau <thern...@mayo.edu> wrote:
> A note on standard errors: S(t) +- std is a terrible confidence > interval. You will be much more accurate if you use log scale. (Some > argue for logit or log-log, in truth they work well.) If n is large > enough, however, you should be ok. Very true, but if one really wants a confidence interval for S_1(t)-S_2(t) (not for S_1(t)/S_2(t)) then one is pretty much forced to use the raw probability scale. -thomas -- Thomas Lumley Professor of Biostatistics University of Auckland ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.