[R-meta] Questions about model averaging with complex multilevel meta-analytic model

[Viechtbauer, Wolfgang (NP)]

Troubleshooting this remotely is difficult.

Does this example run?

https://gist.github.com/wviechtb/891483eea79da21d057e60fd1e28856b

If so, then this is a bit of a head-scratcher given that there is nothing fundamentally different about your model. It just has a lot more fixed effects (and a slightly simpler random effects structure).

Maybe start by simplifying the 'mods' part. First try with just 2 or 3 of the variables and see if that works. If the problem only arises when adding more predictors, then this could be a problem with MuMIn. But first, you have to narrow down where the problem is coming from.

Best,
Wolfgang

>-----Original Message-----
>From: Margaret Slein [mailto:maslein using zoology.ubc.ca]
>Sent: Wednesday, 28 September, 2022 19:56
>To: Viechtbauer, Wolfgang (NP)
>Cc: r-sig-meta-analysis using r-project.org
>Subject: Re: [R-meta] Questions about model averaging with complex multilevel
>meta-analytic model
>
>Hi Wolfgang,
>
>Yes, very large dataset (1700+). Thank you for the advice on the publication
>bias, I will certainly take this into account.
>
>Related to my original question, I have now fit all my candidate models with ML
>rather than REML, which allows me to use model.sel() in the MuMIn package,
>however, I am still unable to use the model.avg() function without the error
>message "Error in x$coefficients[, 1L] : subscript out of bounds”. What would
>cause this error and how can I model average with rma.mv objects and model.avg()
>in the MuMIn package.
>
>Many thanks,
>Maggie
>
><*)))><>  <*)))><>   <*)))><>  <*)))><>
>
>Maggie Slein (she/her/hers)
>PhD Student, O’Connor Lab
>Department of Zoology
>Unceded xʷməθkʷəy̓əm (Musqueam) territory
>University of British Columbia