I am trying to model survival data with a Weibull distribution
using survreg. Units are clustered two apiece, sometimes receiving
the same treatment and sometimes opposing treatment.
Residual and predict methods are not carried out on the survreg
object, although the component linear.predictors exists for the
survreg object. Looking at the code I see that the residual method
refuses to run if any of the components of the pterms vector is
equal to 2.
When taking the logarithm of the data and trying a linear mixed
model, residuals and predicted values are produced just fine.
So what is pterms and why is it that, when any component of it
is 2, residuals are not allowed to be displayed?
--
Johannes Hüsing There is something fascinating about science.
One gets such wholesale returns of conjecture
mailto:johannes at huesing.name from such a trifling investment of fact.
http://derwisch.wikidot.com (Mark Twain, "Life on the Mississippi")