R help - Nov 2005 - NLME

Dear All,
 
Using:-
R : Copyright 2005, The R Foundation for Statistical Computing
Version 2.1.1  (2005-06-20), ISBN 3-900051-07-0
 and 
 
 Jose Pinheiro, Douglas Bates, Saikat DebRoy and Deepayan Sarkar (2005). nlme:
Linear and
 nonlinear mixed effects models. R package version 3.1-65.

on a WINDOWS 2000 machine
 
I am trying to run the scripts from the Mixed Models book and am running into
some difficulty - could any one tell me why this doesn't work (from pages
369 - 370)
 
 
CO2  #FINE
plot(CO2,outer= ~Treatment*Type,layout=c(4,1)) #FINE
 
fm1CO2.lis <- nlsList( SSasympOff, CO2 ) #FINE
fm1CO2.lis #FINE
 

fm1CO2.nlme <- nlme( fm1CO2.lis ) #COPIED DIRECTLY FROM BOOK!!??
 
Gives the error message:-
 
Error in nlme.formula(model = uptake ~ SSasympOff(conc, Asym, lrc, c0),  : 
        Maximum number of iterations reached without convergence

 
Any assistance would be greatly appreciated
 
Guy Forrester
 
 
 
 
 
--------------------------------------------------------
Guy J Forrester
Biometrician
Manaaki Whenua - Landcare Research
PO Box 69, Lincoln, New Zealand.
Tel. +64 3 325 6701 x3738
Fax +64 3 325 2418
E-mail ForresterG@LandcareResearch.co.nz 
www.LandcareResearch.co.nz 



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Guy Forrester <ForresterG <at> landcareresearch.co.nz> writes:
> R : Copyright 2005, The R Foundation for Statistical Computing
> Version 2.1.1  (2005-06-20), ISBN 3-900051-07-0
>  Jose Pinheiro, Douglas Bates, Saikat DebRoy and Deepayan Sarkar (2005). 
...
> I am trying to run the scripts from the Mixed Models book and am running
into
some difficulty - could any one
> tell me why this doesn't work (from pages 369 - 370) 
> 
>  
> CO2  #FINE
> plot(CO2,outer= ~Treatment*Type,layout=c(4,1)) #FINE
These examples were written for S; until version 2.1.1 (the version you are 
using) the optimizing engine for R was different from S, and some of the 
examples did not work. Consult the nlme/scripts, were the non-converging parts 
are commented out.
>From 2.2.0, the R/s engines should be similar, so if you update the examples
from the book should run. My mileage varied, however:

After installing R 2.2.0 (Windows), I immediately tried to run the ping-pong 
examples in ch06.R and ch08.R, because I had encountered quite few of these in 
my own stuff.

fm1Quin.nlme works now.

Strangely, fm2Pheno.nlme still plays merry-go-round. However, when I changed 
pnlsTol to 0.1, it worked. The results were close to those published, but not 
exactly the same. I did not try this in previous versions, maybe it would have 
worked there too with this modification.

Dieter