[R-sig-ME] Increasing iteration limit / lmer bug

[Luca Borger]

Hello,

this same issue has been reported quite recently (29 March 2010), Ben Bolker 
found that there is indeed a bug and provided also a fix for it. Here is the 
link to the mail archives:

https://stat.ethz.ch/pipermail/r-sig-mixed-models/2010q1/003547.html


Cheers,

Luca


----- Original Message ----- 
From: "Adam D. I. Kramer" <adik at ilovebacon.org>
To: <r-sig-mixed-models at r-project.org>
Sent: Wednesday, March 31, 2010 8:14 PM
Subject: Re: [R-sig-ME] Increasing iteration limit / lmer bug


> With apologies, after a lot of grepping around and reading pages on the
> internet, yes, as you expected, my model is to blame.
>
> That said, I think that it is quite appropriate for commands listed in the
> ?help page to actually work or do what they say--in the below case, it is
> clear that maxIter is being ignored.
>
> If it is the case that a "valid" or "good" or "non-stupid" model will 
> easily
> be fit with maxIter=300 and maxFN=900, then there is no reason to allow
> users to think they have changed this value when they have not.
>
> Cordially,
> Adam
>
> On Wed, 31 Mar 2010, Adam D. I. Kramer wrote:
>
>> Dear colleagues,
>>
>> I am attempting to fit a model in this manner:
>>
>> l3 <- glmer(mug ~ condition*time +
>> (time|cafe),family=binomial,data=data)
>>
>> ...the model fails to fit, however, noting:
>>
>> In mer_finalize(ans) : iteration limit reached without convergence (9)
>>
>> ...so, of course, I read the man page for glmer and added
>> control=list(maxIter=3000). However, the program ran for the same amount 
>> of
>> time (about 10 minutes) and produced the same error (and, incidentally, 
>> the
>> same output).
>>
>> So, I believe there to be a bug in glmer such that maxIter is not
>> functioning.
>>
>> I then upped maxFN, too, (also to 3000) in case that was the problem, but
>> found no meaningful difference in the model produced or the time taken to
>> fit the model.
>>
>> Could somebody recommend a workaround? I would like to fit this model.
>>
>> (running R 2.10.1, lme4 v. 0.999375-32)
>>
>> Also, in case it matters, 'time' here is a categorical variable
>> reperesenting several within-subjects timepoints--there are some other
>> (unanswered) posts to this list in which people appear to have fairly
>> complex within-subjects effects. Perhaps the issue is that the defaults
>> which are in place are insufficiently high for moderately complex
>> within-subjects models?
>>
>> Cordially,
>> Adam D. I. Kramer
>>
>> _______________________________________________
>> R-sig-mixed-models at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models
>>
>
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