[R-meta] fixed-effect multivariate model interpretation
Thank you Wolfgang! So my related question is how this residual heterogeneity is estimated in order to compute the Q statistic? Because if the model is still estimating and testing the presence of heterogeneity, from a multivariate model I would have expected one residual heterogeneity term for each outcome (the same as I have one tau per outcome if I fit the random-effect version). On Mon, 3 Jan 2022 at 16:50, Viechtbauer, Wolfgang (SP) <
wolfgang.viechtbauer at maastrichtuniversity.nl> wrote:
Hi Filippo, You can *assume* that there is no residual heterogeneity, but there may be. That is what the test of residual heterogeneity is testing here (whether your assumption is correct or not). Best, Wolfgang
-----Original Message----- From: R-sig-meta-analysis [mailto:
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Behalf Of Filippo Gambarota Sent: Monday, 03 January, 2022 16:42 To: R meta Subject: [R-meta] fixed-effect multivariate model interpretation Hello! I'm fitting for the first time a multivariate fixed-effect model using metafor. The code is: ``` rma.mv(yi, V, mods = ~ 0 + outcome, data = data, test = "t") ``` Where V is the block variance-covariance matrix created with vcalc() that represents the covariance between different outcome levels within each study. The outcome is a factor that represents different effect sizes measured on the same participants within a study. The model as expected did not estimate tau for each outcome and test all coefficients (each outcome mean with this parametrization) against 0 (both the omnibus test and each beta). My question is about the *residual heterogeneity* parameter and the associated Q test. Under this model, I should have assumed that there is no heterogeneity within each outcome level so I'm not sure how to interpret the residual heterogeneity in this case. Thank you! Filippo -- Filippo Gambarota PhD Student - University of Padova Department of Developmental and Social Psychology Website: filippogambarota.netlify.app Research Group: Colab Psicostat
*Filippo Gambarota* PhD Student - University of Padova Department of Developmental and Social Psychology Website: filippogambarota.netlify.app Research Group: Colab <http://colab.psy.unipd.it/> Psicostat <https://psicostat.dpss.psy.unipd.it/> [[alternative HTML version deleted]]