Dear R-users, I have noticed small discrepencies in the reported estimate of the variance of the frailty by the print method for survreg() and the 'theta' component included in the object fit:
# Examples in R-2.6.2 for Windows library(survival) # version 2.34-1 (2008-03-31) # discrepancy fit1 <- survreg(Surv(time, status) ~ rx + frailty(litter), rats) fit1 fit1$history[[1]]$theta # OK fit2 <- survreg(Surv(time, status) ~ rx + frailty(litter, df = 13), rats) fit2 fit2$history[[1]]$theta # discrepancy fit3 <- survreg(Surv(time, status)~ age + sex + frailty(id), kidney) fit3 fit3$history[[1]]$theta # OK fit4 <- survreg(Surv(time, status)~ age + frailty(id), kidney) fit4 fit4$history[[1]]$theta Am I missing something? Thanks in advance for any pointers! Best, Dimitris ---- Dimitris Rizopoulos Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/(0)16/336899 Fax: +32/(0)16/337015 Web: http://med.kuleuven.be/biostat/ http://www.student.kuleuven.be/~m0390867/dimitris.htm Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ______________________________________________ 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.
