Hi All, I am trying to run the following script but have problem,
coxm<- coxph(Surv(sdat$time, sdat$cens)~hd+nawtg+nwwg+ntpg+cy+nseas,data=sdat) coxm<-stepAIC(coxm,~.^2) The error message is Error: could not find function "stepAIC" I tried to install the package but I could not find it. Where can i get it? The other question is that I want to get the Kaplan-Meier Estimate for each covariate in the model, Like covaraite n Events Mean, S.E.(mean) ,Median, 95% LCL, 95% UCL 0 14 10 2.87 .03 2.2 1.938 infi 1 11 9 1.06 .67 1.1 0.29 2.48 I used sdat.fit0 <- survfit(Surv(sdat$time, sdat$cens)~sdat$ntpg, data = sdat, type = "kaplan-meier", conf.type="plain") sdat.fit0 Instead I got the following, Call: survfit(formula = Surv(sdat$time, sdat$cens) ~ sdat$ntpg, data = sdat, type = "kaplan-meier", conf.type = "plain") records n.max n.start events median 0.95LCL 0.95UCL sdat$ntpg=0 3576 3576 3576 311 NA NA NA sdat$ntpg=1 4851 4851 4851 466 NA NA NA I would appreciate if some one can help me. thanks ______________________________________________ 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.