Dear Wolfgang and list members, Is there any function or code for rma.mv models that would work like lme4::isSingular()? I ask this because, given a fixed number of moderators, I sometimes want to empirically explore how much room for adding random effects in rma.mv I have before my model becomes singular but I don't know how to do that. Thank you so much, Stefanou
[R-meta] Determining if an rma.mv model is singular
3 messages · Stefanou Revesz, Michael Dewey
Dear Stefanou Would it not be simplest just to fit the models and see what happens? You are not going to break anything. Michael
On 22/03/2022 00:50, Stefanou Revesz wrote:
Dear Wolfgang and list members, Is there any function or code for rma.mv models that would work like lme4::isSingular()? I ask this because, given a fixed number of moderators, I sometimes want to empirically explore how much room for adding random effects in rma.mv I have before my model becomes singular but I don't know how to do that. Thank you so much, Stefanou
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Michael, Given the history behind the "sneaky" nature of singular models and how easily people fall victim to it (https://arxiv.org/pdf/1506.04967.pdf), I would think it may not be advisable to simply fit the models and see what happens, indeed nothing noticeable may happen at times (https://stats.stackexchange.com/a/449122/140365) and that's probably why lme4::isSingular() exists. Stefanou
On Tue, Mar 22, 2022 at 8:25 AM Michael Dewey <lists at dewey.myzen.co.uk> wrote:
Dear Stefanou Would it not be simplest just to fit the models and see what happens? You are not going to break anything. Michael On 22/03/2022 00:50, Stefanou Revesz wrote:
Dear Wolfgang and list members, Is there any function or code for rma.mv models that would work like lme4::isSingular()? I ask this because, given a fixed number of moderators, I sometimes want to empirically explore how much room for adding random effects in rma.mv I have before my model becomes singular but I don't know how to do that. Thank you so much, Stefanou
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