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Dear James, Thank you very much. This is very helpful to know, almost any thread I looked at in the archives talked about the systematic bias in the estimates of variance components and the necessity of using RVE to account...

Super helpful! For some reason, the devel version doesn't get installed on my machine (must be an R issue; mine's a version 4.0). At some point, one might say which regression is more useful, the one on...

Many thanks for the valuable insights. Stefanou On Tue, Nov 23, 2021 at 3:42 PM Lukasz Stasielowicz <lukasz.stasielowicz at uni-osnabrueck.de> wrote: > > Dear Stefanou, > > as Michael Dewey has pointed out, comparing regression coefficients > based on models with...

Thanks! Reporting back the results for two models (note: "time_wk" = "time_meaning_wks"). In model 1, I used "time_wk" to the left of | for "CAR". In model 2, I used "time_whtn" to the left of | for "CAR...

Thanks! Feel free to ignore this, but I don't think it has come up on the mailing list before. If I use: list(~ 1 | study, ~1|outcome, ~ 1 | measure), then everything else aside, it means I believe that there...

Sure, it's alway been easier to use a personal account for a non-university business but if needed (which I honestly didn't know) in the future posts I will subscribe using my UCL account. At any rate, thanks...

Oops. I was referring to your linked post: https://stat.ethz.ch/pipermail/r-sig-meta-analysis/2018-July/000896.html study outcome measure study.outcome.measure 1 A 1 1.A.1 1 B 1 1.B.1 2...

Dear Wolfgang, Reza and James, Thank you so much, I think I got really great, complementary advice. I'm convinced that I should reverse the sign of effect sizes on one of my outcomes to avoid all the complexities that...

Thank you so much! One clarification question. matreg() is not effect-size specific, correct? I mean you may have meta-analyzed any type effect size (SMD, ROM, OR, ...) and then subject the vcov() or G or H matrices of those...

Thanks. In my case, each 'outcome' means the same thing across the studies. I take 'measure' as a crossed random effect, because I believe each 'measure' has its own inherent characteristics (its own questioning style, its own length etc) that...

Thanks Wolfgang, But is what I have done a methodologically reasonable way to do this, or a more reasonable way exists. It's great that vcov() or random effects var-covariance matrix can be obtained from an rma.mv() fit...

Dear Wolfgang, Thank you very much! In your answer, you also demystified the problem of why model2 crashes, if I don't round the "time_wthn" up to 8 decimal places (that had me thinking the whole day yesterday). I...

Sure, to confirm differences between the two models, can we say model `res` (i.e., list(~ 1 | study, ~1|outcome, ~ 1 | measure)) views the random effects this way: res_model <- with(m, interaction(study,outcome,measure)) But model `res2` (i...

Dear Wolfgang, Thank you for your reply. I did check that previously. But my question is why 'outcome' gives the same variance component across both res (with 4 levels) and res2 (with 68 levels) models? Thank you so much, Stefanou...

Sure, but in the lme(), "correlation=" has to do with the structure of V matrix (i.e., e_ij), not random-effects, no? Say, I had used the categorical "time" (measurement occasions) with struct = "HAR", then would it have made...

Interesting, thanks! This possibility never came up on the list (at least based on my thorough search). This possibility make me wonder what methodological guidelines might be out there regarding the pros and cons of using 'outcome' as a crossed...

Very interesting! Thanks a lot! Just a very final question, what does the ~ 1 | id part do or assume? On Sun, Sep 12, 2021 at 6:13 PM Reza Norouzian <rnorouzian at gmail.com> wrote: > > I wonder how conditions could...

Wolfgang, you're a lifesaver! That's such a confusing coincidence! As we inch toward the last few studies, the variance component for 'outcome' across `res` (fully crossed model), and `res2` (nested + crossed model) get more and more similar. Does...

Dear Wolfgang, Thank you for your reply. The rma.mv() documentation for CAR says: "the values of the "inner" variable should reflect the exact time points of the measurement". 1) Does that mean I should use: "time_meaning_wks | study...

Hi Reza, Thank you so much! A quick follow-up, when you say "If in each study, true SMCCs at all intervals across the conditions are assumed to have their own auto-regressively correlated structure as well", I wonder how...