Thank you again for your help. Your suggestions worked perfect. The problems I had when using f.pom=factor(-3, levels=seq(-3,2.5, by=0.5)) were a silly mistake on my part (as suspected and dually pointed out). Thanks for the notes on baseline. I was not aware of the inaccuracies when using it at z=0.
I will be back with questions on computationally efficient time dependant survival functions next month. Cheers, Kylie-Anne ----- Original Message ----- From: "Thomas Lumley" <[EMAIL PROTECTED]> To: "Kylie-Anne Richards" <[EMAIL PROTECTED]> Cc: <r-help@stat.math.ethz.ch> Sent: Sunday, July 17, 2005 1:19 AM Subject: Re: [R] Coxph with factors > On Sat, 16 Jul 2005, Thomas Lumley wrote: >> >> Yes, but you don't need to go via the baseline. The survival curves for >> any two covariate vectors z1 and z2 are related by >> >> S(t; z1)= S(t; z2)^(z1-z2) >> > Actually > S(t; z1)=S(t;z2) ^(beta'(z1-z2)) > > of course. > > -thomas > ______________________________________________ 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
