Dear users, I am fitting a conditional gap time frailty cox model weighting observations by means of inverse probability time dependent weigths. Attached find the self-explaining dataset.
I have used the following sintax: coxph(Surv(gaptstart,gaptstop,status)~treat+strata(nrecord01)+frailty(id,distribution="gamma",method="em"), data=dataNOTDrr,weights=dataNOTDrr$weight) And I get the following warning: Warning message: In coxpenal.fit(X, Y, strats, offset, init = init, control, weights = weights, : Inner loop failed to coverge for iterations 3 4 I have tried to: - leave out the weights but I get the error anyway - to randomly select a subset of patients and I don't get the error. This seems to suggest that the problem is with some observations. Any suggestion? Many thanks, Elisabetta ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
