Hi, I am currently using R v3.2.3 and on Windows 10 OS 64Bit.
I am having convergence issues when I use coxph with a interaction term (glarg*bca_py) and interaction term with the restricted cubic spline (glarg*bca_time_ns). I use survival and spline package to create the Cox model and cubic splines respectively. Without the interaction term and/or spline, I have no convergence problem. I read some forums about changing the iterations and I have but it did not work. I was just wondering if I am using the inter.max and outer.max appropriately. I read the survival manual, other R-help and stackoverflow pages and it suggested changing the iterations but it doesn't specify what is the max I can go. I ran something similar in SAS and did not run into a convergence problem. This is my code: bca_time_ns <- ns(ins_ca$bca_py, knots=3, Boundary.knots=range(2,5,10)) test <- ins_ca$glarg*ins_ca$bca_py test1 <- ins_ca$glarg*bca_time_ns coxit <- coxph.control(iter.max=10000, outer.max=10000) bca<-coxph(Surv(bca_py,bca) ~ glarg + test + test1 + age + calyr + diab_dur + hba1c + adm_met + adm_sulfo + adm_tzd + adm_oth + med_statin + med_aspirin + med_nsaids + bmi_cat + ccscat + alc + smk, data=ins_ca, control=coxit, ties=c("breslow")) This is the error message I get: Warning message: In fitter(X, Y, strats, offset, init, control, weights = weights, : Ran out of iterations and did not converge [[alternative HTML version deleted]] ______________________________________________ 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.