Hi,
The reason I didn't send this to r-help is I am not interested in just
evaluating the variance function
for a particular set of data. That is not a big deal,
for your example,
pp<-predict(fm1,list(weight=c(15,16)))
vf<-pp^2*(coef(fm1$modelStruct$varFunc))
which is not the point. The point is t
Yes, this probably should go to R-help, and before you do that, I
suggest you PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html. It can increase the
likelihood you will get a useful reply relatively quickly.
I tried the your two calls to "gnls",
Hi,
I guess this is a final plea, and maybe this should go to R-help but
here goes.
I am writing a set of functions for calibration and prediction, and to
calculate standard
errors and intervals I need the variance function to be evaluated at new
prediction points.
So for instance
fit<-gnls(Y~SSl
