Hello there,

Using 'The R Book' (p675-677) I am following instructions on performing a
series of nonlinear regressions fitting the same model to a set of groups. I
have been to able to fit the model to my data using the following call to
nlme:
 >library(nlme)
 >inorg.model<-nlme(inorg.grv ~ a*exp( - ((numDate-b)^2 / 2*c^2)),
fixed=a+b+c~1,
random=a~1|Sectionf,
start=c(a=adi,b=bdi,c=cdi), verbose = TRUE)

Now, again following the R book, I would like to plot these models using
augPred. However I receive the following error:

>plot(augPred(inorg.model))
Error in augPred.lme(inorg.model) :
Data in inorg.model call must evaluate to a data frame

I am not sure even how to diagnose this problem. I basically followed to R
book directions to the letter. I could plot each of these curves from each
out individually but the prospect of R doing it all for me is too tempting.

I am using R 2.8.1-1 and Ubuntu 9.04.

Thanks in advance!

Sam

-- 
*****************************************************
Sam Albers
Geography Program
University of Northern British Columbia
3333 University Way
Prince George, British Columbia
Canada, V2N 4Z9
phone: 250 960-6777
*****************************************************

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