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Effect size from post-hoc tests

Open esiotort opened this issue 9 years ago • 3 comments

Hello!

Is there any way to calculate generalised eta-squared for contrasts run on afex anova's using the lsmeans/multcomp procedures detailed in your post-hoc tests vignette?

Cheers

esiotort avatar Apr 14 '16 11:04 esiotort

Unfortunately not at the moment (and I do not think anytime soon). The reason is that those types of standardized effect sizes require sums of squares which are not reported by lsmeans or multcomp.

Instead, I would simply report the estimate from the lsemans output as effect. If you necessary need a standardized effect size (which might not be the best thing in the world) an effect size based on the output from lsmeans (i.e., estimate and SE) may be possible, but this may depends on your design (within- or between-factors) and what you believe is a good standardized effect size. To state this clearly, I am not a big fan of standardized effect sizes.

PS: I will leave this open for future reference and people looking for the same thing.

singmann avatar Apr 14 '16 11:04 singmann

Thanks for the answer

esiotort avatar Apr 14 '16 15:04 esiotort

See also a somewhat longer response at: https://afex.singmann.science/forums/topic/compute-effect-sizes-for-mixed-objects/#post-295

singmann avatar Jul 28 '18 21:07 singmann