I am unable to get the basehaz function to apply a proportional hazards model to a new data frame. I replicated my specific situation with the example for coxph in the help, where I changed the x value of the first record from 0 to 1. Is there something incorrect in the syntax that I am using? Thanks in advance!
test1 <- list(time= c(4, 3,1,1,2,2,3), status=c(1,NA,1,0,1,1,0), x= c(0, 2,1,1,1,0,0), sex= c(0, 0,0,0,1,1,1)) test2 <- list(time= c(4, 3,1,1,2,2,3), status=c(1,NA,1,0,1,1,0), x= c(1, 2,1,1,1,0,0), sex= c(0, 0,0,0,1,1,1)) f1 <- coxph( Surv(time, status) ~ x + strata(sex), data=test1) #stratified model f2 <- coxph( Surv(time, status) ~ x + strata(sex), data=test2) #stratified model f1 Call: coxph(formula = Surv(time, status) ~ x + strata(sex), data = test1) coef exp(coef) se(coef) z p x 1.17 3.22 1.29 0.907 0.36 Likelihood ratio test=0.87 on 1 df, p=0.351 n=6 (1 observation deleted due to missingness) > f2 Call: coxph(formula = Surv(time, status) ~ x + strata(sex), data = test2) coef exp(coef) se(coef) z p x 0.896 2.45 1.42 0.63 0.53 Likelihood ratio test=0.38 on 1 df, p=0.535 n=6 (1 observation deleted due to missingness) > > basehaz(f1, newdata=test2) Error in basehaz(f1, newdata = test2) : unused argument(s) (newdata = list(time = c(4, 3, 1, 1, 2, 2, 3), status = c(1, NA, 1, 0, 1, 1, 0), x = c(1, 2, 1, 1, 1, 0, 0), sex = c(0, 0, 0, 0, 1, 1, 1))) > ______________________________________________ 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.