[R-meta] Extracting residuals from rma.mv function

Dear Rafael,

I don't understand the details of what you are trying to do, but you can
obtain residuals from a 'rma.mv' model with resid(). However, that will
only give you the residuals and no indication of their precision. With
rstandard(), you can get get the residuals ('resid') and the corresponding
standard errors ('se'). If the model you have fitted accounted for
phylogenetic non-independence and differences in the precision of the
effect sizes, then so will the residuals and corresponding standard errors.

However, note that residuals are not independent (that is even the case in
simple regression models outside of the meta-analytic context). With:

vcov(res, type="resid")

(assuming the model object is called 'res') you can get the full var-cov
matrix of the residuals. You will note that this is not a diagonal matrix.
The standard errors are just the square root of the diagonal elements:

sqrt(diag(vcov(res, type="resid")))

So, whatever you intend to do with the residuals may require that you not
only account for differences in their precision, but also their covariances.

Best,
Wolfgang

-----Original Message-----
From: Rafael Rios Moura [mailto:biorafaelrm at gmail.com]
Sent: Saturday, 05 December, 2020 18:26
To: r-sig-meta-analysis at r-project.org; Viechtbauer, Wolfgang (SP)
Subject: Extracting residuals from rma.mv function

Dear Dr. Wolfgang and All,

I want to extract unbiased residuals of a rma.mv function to use in a
repeatability analysis for another random variable in the rptR package.
Thus, I want to control for precision (or weight) for each effect size and
phylogenetic non-independence. Which kind of residuals should be more
appropriate to do that in a mixed-effects multilevel meta-analysis and how
can I extract them from the rma.mv function? Any help is welcome.

All the best,