search for: basehazzft

Displaying 1 result from an estimated 1 matches for "basehazzft".

2009 Oct 27
2
cox regression extract strata as numeric
...I perform a stratified cox and then I need the strata as a  numeric array "straft.ln" ft.ln <- coxph(Surv(times,deaths)~ages+chemos+chemos:f1+chemos:f2+horms+horms:f1+horms:f2+grades+grades:f1+grades:f2+positives+positives:f1+positives:f2+sizes+sizes:f1+sizes:f2+strata(stra),data=ddd) basehazzft.ln=basehaz(ft.ln,centered=FALSE) H0ft.ln=c(basehazzft.ln[,1]) timeft.ln=c(basehazzft.ln[,2]) straft.ln=c(basehazzft.ln[,3]) I notice that basehazzft.ln[,3] is not the same with straft.ln with respect to the values i.e.: (basehazzft.ln$stra[1]) [1] stra=1 134 Levels: stra=1 stra=10 stra=100 stra=1...