Maximum nAGQ=25?
Ben Bolker <bbolker at ...> writes:
Ross Boylan <ross <at> ...> writes:
On Thu, Sep 26, 2013 at 04:23:47PM +0000, Ben Bolker wrote:
Rafael Sauter <rafael.sauter <at> ...> writes:
[snip]
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?
[snip]
If the limit is hard-coded to 25, it will be hard to discover if using
25 matters. That seems to me an argument for not hard coding it. I
suppose if the results had not stabilized by 25 that would be an indication. OTOH, 25 is a lot of quadrature points.
OK, Doug Bates has chimed in at https://github.com/lme4/lme4/issues/136 to point out that the current implementation of AGHQ is table-driven (see https://github.com/lme4/lme4/blob/master/R/GHrule.R ); thus, the decision to limit the number of quadrature points is *not* arbitrary, and extending it is not just a matter of removing the test for nAGQ>25. The table could be extended, or a new implementation could compute the table on the fly -- but for now this will probably go back down the priority list a bit unless someone demonstrates a really pressing need or sends us a pull request ... Ben Bolker