Dear R-sig-ME,

since the beginning of this year the new lme4-version is available on
CRAN which has some major changes compared to older versions.
I am still running the old lme4-version ‘0.999999.2’.

Now I am surprised by one of the changes in the current new version
'1.0-4': 
the GH-approximation allows only for a maximum of 25 quadrature points
(nAGQ=25) whereas in the old version I did not encounter any such
restrictions for the number of quadrature points.
As I did not find any discussion about this change in the new
lme4-version let me allow to ask:

1) Why is 25 a reasonable upper bound for nAGQ? What were the reasons to
implement this upper bound? Is the increasing complexity as mentioned in
the details of '?glmer' the the main reason for this?

2) Is this somehow related to the fact that at the moment in the new
lme4 version nAGQ>1 is only available for models with a single, scalar
random-effects term (as discussed here
https://stat.ethz.ch/pipermail/r-sig-mixed-models/2013q3/020573.html and
will this maximum of nAGQ=25 stay that way in the future also when
non-scalar random effects will be implemented again?

I'd be glad for any hints and explanations about this issue.
Thanks,

Rafael Sauter

University of Zurich
PhD student
Institute of Social and Preventive Medicine
Division of Biostatistics
Hirschengraben 84
8001 Zurich
Switzerland
Phone: 0041 44 634 54 86
rafael.sauter@uzh.ch

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