Hi everybody, I am a new user of R, design package. I am trying to plot the estimated hazard ratio's of my cox regression model with the confidence intervals. But I keep getting the message:Error in `contrasts<-`(`*tmp*`, value = "contr.treatment") : contrasts can be applied only to factors with 2 or more levels
I have dichotomous, categorical as well as continuous variables in the model, but I can only plot the dichotomous variable. I started with the following syntax: dd <- datadist(x1, x2, x3) options(datadist='dd') fit<-cph(S~ x1 +x2 +x3, x=T,y=T) plothr<- summary(fit) plot(plothr, log=T) Because the levels defined by datadist didn't seem to work I tried to adjust the levels after fitting the model: dd$limits["Adjust to","x1"] <- 1 dd$limits["Adjust to","x2"] <- 30 fit <- update(fit) plothr<- summary(fit) plot(plothr, log=T) Finally I have tried: summary(fit, x1=1, x2=30, x3=3) But this option didn't work either. Can anybody tell me what goes wrong and why? Thanks for your help, Cary Cary Dehing-Oberije Researcher CAT project p/a MAASTRO clinic Dr. Tanslaan 12 6229 ET Maastricht The Netherlands phone: 088 - 4455666 / 088 - 4455767 email: [EMAIL PROTECTED] [[alternative HTML version deleted]] ______________________________________________ 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.