R help - Nov 2006 - Using a deriv function in nlme

Hello,

 

I have a deriv function that I am feeding to nlme. It works, and I can use
it in nls, but when I try to use it in nlme I get Error: subscript out of
bounds.  I can fit the model using SSasympOrig, instead of the deriv
function, but I am trying to reproduce an earlier analysis (done in Splus)
and I get slightly different results with SSasympOrig.

 

Here are my calls:

 

This does fit the nlme model:

L1.lis<-nlsList(SSasympOrig,L1.gd)

L1.nlme<-nlme(L1.lis)                 

 

Here is the derive function -it works for the nls call:

boundedexp<-deriv(~100/(1+exp(-L))*(1-exp(-exp(logR)*x)), 

                        c("L", "logR"), function(x,L,logR){}
)

 

L1.nls<-nls(ability ~ boundedexp(age,limit,lograte),

            data=L1.gd, start=c(limit=2,lograte=-3))

summary(L1.nls)

 

. but here I run into problems

L1.nlme2<-nlme(ability~boundedexp(age,limit,lograte),

            data=L1.gd, fixed=limit+lograte~1,start=c(limit=2,lograte=-3))

 

Any suggestions would be well appreciated!


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Lisa Avery <lisa_avery <at> sympatico.ca> writes:
> 
> Hello,
> 
> I have a deriv function that I am feeding to nlme. It works, and I can use
> it in nls, but when I try to use it in nlme I get Error: subscript out of
> bounds.  I can fit the model using SSasympOrig, instead of the deriv
It might by a similar problem as in 

http://finzi.psych.upenn.edu/R/Rhelp02a/archive/4555.html

Dieter Menne