[R-meta] (partial) eta squared
Hello Wolfgang, thank you very much for your reply. It seems like eta squared might not be the most straightforward option then when intending to work with metafor. Would you recommend another effect size for an interaction effect from a linear regression that is more compatible with the analyses metafor runs? All the best, Antonia On 3 August 2018 at 15:09, Viechtbauer, Wolfgang (SP) <
wolfgang.viechtbauer at maastrichtuniversity.nl> wrote:
Dear Antonia, in principle, you could meta-analyze eta^2 values, but there are several issues to consider: 1) The sampling distribution of eta^2 isn't normal. So, one would first have to explore what kind of transformation would be appropriate for eta^2 values to normalize their sampling distribution. 2) I do not know off the top of my head an equation for the sampling variance of eta^2 values. 3) eta^2 isn't a directional effect size measure. Two eta^2 values of the same magnitude could imply entirely opposite findings. So, one could question the usefulness of aggregating eta^2 values in the first place. Best, Wolfgang -----Original Message----- From: R-sig-meta-analysis [mailto:r-sig-meta-analysis- bounces at r-project.org] On Behalf Of Antonia Sudkaemper Sent: Friday, 03 August, 2018 12:33 To: r-sig-meta-analysis at r-project.org Subject: [R-meta] (partial) eta squared Hello fellow meta-analysis colleagues, I have recently started using metafor and am still exploring. Currently, I am working on a mini meta-analysis of three studies I ran myself. In recent psychology journal I have seen the use of (partial) eta squared as an indicator of effect size. I was wondering if I can use the rma.uni command to run a meta-analysis on (partial) eta squared? And if so, which error (vi/sei) indicator would I use with it? Hope someone can help! All the best, Antonia -- Antonia Sudk?mper PhD Candidate in Organizational Psychology/University of Exeter www.antoniasudkaemper.com a.sudkaemper at gmail.com
Antonia Sudk?mper PhD Candidate in Organizational Psychology/University of Exeter www.antoniasudkaemper.com a.sudkaemper at gmail.com [[alternative HTML version deleted]]