On Thu, Dec 8, 2011 at 3:55 AM, ifejobi <ifej...@gmail.com> wrote: > Hello, > > I'm working with some left censored survival data using accelerated failure > time models. I am interested in fitting different distributions to the data > but seem to be getting the same results from the model fit using survreg > regardless of the assumed distribution. > > These two codes seem to provide the same results: > > aft.gaussian <- summary(survreg(Surv(y,y>0),type="left")~ > group),dist="gaussian") > > aft.weibull <- summary(survreg(Surv(y,y>0),type="left")~ > group),dist="weibull") >
That's because you're fitting the same model: the dist= argument needs to be inside the parentheses for survreg(). -thomas -- Thomas Lumley Professor of Biostatistics University of Auckland ______________________________________________ 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.