Re: [R] coxph and survfit issue - strata
> Dear users, > > In a study with recurrent events: > My objective is to get estimates of survival (obtained through a Cox > model) by rank of recurrence and by treatment group. > With the following code (corresponding to a model with a global > effect of the treatment=rx), I get no error and manage to obtain > what I want : > data<-(bladder) > model1<-coxph(Surv(stop,event)~rx+strata(enum) > +cluster(id),data=bladder) > data1<-data.frame(rx=1) > survfit(model1,newdata=data1) > > But with the model with strata by treatment interaction > (corresponding to a model with an effect of the treatment by rank), > I get the following error: > model2<-coxph(Surv(stop,event)~rx*strata(enum) > +cluster(id),data=bladder) > > data1<-data.frame(rx=1) > > survfit(model2,newdata=data1) > Erreur dans strata(enum) : objet "enum" non trouv? =>error in > strata(enum) : object "enum" not found You have neglected to tell us what version of R and of the survival library you are using. (As the author, I always have the newest version of course.) The example you gave works if there is no "cluster" statement. Your error is a surprise to me and I will look into it. Terry Therneau __ 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.
Re: [R] coxph and survfit issue - strata
On May 6, 2011, at 6:22 PM, Eva Bouguen wrote: Dear users, In a study with recurrent events: My objective is to get estimates of survival (obtained through a Cox model) by rank of recurrence and by treatment group. With the following code (corresponding to a model with a global effect of the treatment=rx), I get no error and manage to obtain what I want : data<-(bladder) model1<-coxph(Surv(stop,event)~rx+strata(enum) +cluster(id),data=bladder) data1<-data.frame(rx=1) survfit(model1,newdata=data1) But with the model with strata by treatment interaction (corresponding to a model with an effect of the treatment by rank), I get the following error: model2<-coxph(Surv(stop,event)~rx*strata(enum) +cluster(id),data=bladder) data1<-data.frame(rx=1) survfit(model2,newdata=data1) Erreur dans strata(enum) : objet "enum" non trouvé =>error in strata(enum) : object "enum" not found Right. Looks like a perfectly clear error message to me you created a newdata dataframe that did not have all the necessary columns that you used on the RHS of your formula. -- David Winsemius, MD West Hartford, CT __ 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.
[R] coxph and survfit issue - strata
Dear users, In a study with recurrent events: My objective is to get estimates of survival (obtained through a Cox model) by rank of recurrence and by treatment group. With the following code (corresponding to a model with a global effect of the treatment=rx), I get no error and manage to obtain what I want : data<-(bladder) model1<-coxph(Surv(stop,event)~rx+strata(enum)+cluster(id),data=bladder) data1<-data.frame(rx=1) survfit(model1,newdata=data1) But with the model with strata by treatment interaction (corresponding to a model with an effect of the treatment by rank), I get the following error: model2<-coxph(Surv(stop,event)~rx*strata(enum)+cluster(id),data=bladder) data1<-data.frame(rx=1) survfit(model2,newdata=data1) Erreur dans strata(enum) : objet "enum" non trouvé =>error in strata(enum) : object "enum" not found Would you have any idea to help me? Thanks in advance, Eva [[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.
