Re: [R] Negative binomial GLMMs in R

From: Anders Nielsen <andersn_at_hawaii.edu>
Date: Mon 28 Mar 2005 - 07:34:57 EST

Dear List,

I have tried the program (Linux version) supplied to fit the negative binomial mixed model. It seems to work really well and converge fast.

Since this is apparently a model that is difficult to fit with what is presently in R, and more difficult to fit with other standard tools, it would be nice to have this solution wrapped into a real R-package with documentation and all. I for one would like to encourage the authors to make such a package available (and would be willing to help if requested).

I don't know if such a package could be posted on CRAN since it relies on a closed source library for automatic differentiation, but if that is a problem it could at least be made available on a personal web-page.

Cheers,

Anders.

On Wed, 23 Mar 2005 Hans.Skaug@mi.uib.no wrote:

> Dear R-users,
>
> A recent post (Feb 16) to R-help inquired about fitting
> a glmm with a negative binomial distribution.
> Professor Ripley responded that this was a difficult problem with the
> simpler Poisson model already being a difficult case:
>
> https://stat.ethz.ch/pipermail/r-help/2005-February/064708.html
>
> Since we are developing software for fitting general nonlinear random
> effects models we thought this might be an interesting challenge.
> We contacted Professor Ripley who kindly directed us to the epilepsy data
> in Venables & Ripley section 10.4 (4th ed.). While V&B did not actually
> fit a negative binomial to these data they did refer to evidence
> of overdispersion in the response. Fortunately Booth et al. (2003) did
> attempt to fit this model with a negative binomial which gave us something
> to which we could compare our results. Booth et al. fitted two forms of
> the model a simpler one and a more complicated model. They reported some
> difficulty fitting the more complicated model. We found that we could
> reliably fit (MLE) both the complicated and simpler model in 20 seconds
> or less (although the more complicated turns out to be overparameterized)
>
> Using the random effects module of AD Model Builder we have developed

> a shared library (Windows dll) that can be called from R via the driver
> function glmm.admb(). The function can be downloaded from
>
> http://otter-rsch.com/admbre/examples/nbmm/nbmm.html
>
> The two models of Booth et al are fit by the commands:
>
> glmm.admb(y~Base*trt+Age+Visit,random=~1,group="subject",data=epil2)
> glmm.admb(y~Base*trt+Age+Visit,random=~Visit,group="subject",data=epil2)
>
> I will be happy to receive feedback on the function glmm.admb().
>
>
> Best regards,
>
> Hans Skaug
>
>
>
> Reference:
> Booth J.G.; Casella G.; Friedl H.; Hobert J.P, Negative binomial loglinear
> mixed models.
> Statistical Modelling, October 2003, vol. 3, no. 3, pp. 179-191
>
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R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Mon Mar 28 07:42:25 2005

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