R help - May 2003 - Error using glmmPQL

Can anyone shed any light on this?
> doubt.demographic.pql<-glmmPQL(random = ~ 1 | groupid/participantid,
+                                fixed = r.info.doubt ~
+            realage + minority + female + education + income + scenario,
+                                data = fgdata.df[coded.resource,],
+                                na.action=na.omit,
+                                niter=50,
+                                family=binomial(link=probit))
iteration 1
iteration 2
iteration 3
iteration 4
iteration 5
iteration 6
iteration 7
iteration 8
Error in logLik.reStruct(object, conLin) :
        NA/NaN/Inf in foreign function call (arg 3)

The traceback() output is very long, so I won't post it, but you can see
it here:

http://www.unc.edu/~aperrin/stuff/diagnostics

Thanks,
Andy Perrin

----------------------------------------------------------------------
Andrew J Perrin - http://www.unc.edu/~aperrin
Assistant Professor of Sociology, U of North Carolina, Chapel Hill
clists at perrin.socsci.unc.edu * andrew_perrin (at) unc.edu

lme does this (and that is from lme) sometimes -- often when the model 
does not fit well.

On Fri, 30 May 2003, Andrew Perrin wrote:
> Can anyone shed any light on this?
> 
> > doubt.demographic.pql<-glmmPQL(random = ~ 1 |
groupid/participantid,
> +                                fixed = r.info.doubt ~
> +            realage + minority + female + education + income + scenario,
> +                                data = fgdata.df[coded.resource,],
> +                                na.action=na.omit,
> +                                niter=50,
> +                                family=binomial(link=probit))
> iteration 1
> iteration 2
> iteration 3
> iteration 4
> iteration 5
> iteration 6
> iteration 7
> iteration 8
> Error in logLik.reStruct(object, conLin) :
>         NA/NaN/Inf in foreign function call (arg 3)
> 
> The traceback() output is very long, so I won't post it, but you can
see
> it here:
> 
> http://www.unc.edu/~aperrin/stuff/diagnostics
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595