Effect sizes + confidence intervals for ANOVA posthoc effect
Posted: Mon Mar 25, 2019 5:20 am
Dear JAMOVI,
(we're using JAMOVI with students in our mass replication project http://mgto.org/pre-registered-replications/ , and this is a common repeating nuisance JAMOVI request with almost every project, so this is on behalf of us all, not just myself).
I would like to request that you calculate and report Cohen's d effects and Cohen's d confidence intervals for posthoc/contrasts/marginal-means in an ANOVA. The np2/w only gives the overall differences between all conditions, but often times the most important effect of interest is the effect of the contrast between two effects. Sure, one could run a t-test and get that (alas, with no CIs, see comment below), but with 3 it's already 3 t-test to run, which gets even more complicated if you have an additional factor (two way ANOVA) or 4 or more conditions in a single factor, becoming a real chore. Simply adding d and d CIs to the existing tables would be terrific.
[I would also like to remind and reiterate the need for CIs for all effects reported (viewtopic.php?f=2&t=495). It's a shame to have to ask students to use online calculators to compute Cohen's d CIs outside of JAMOVI.]
Thanks,
Gilad
(we're using JAMOVI with students in our mass replication project http://mgto.org/pre-registered-replications/ , and this is a common repeating nuisance JAMOVI request with almost every project, so this is on behalf of us all, not just myself).
I would like to request that you calculate and report Cohen's d effects and Cohen's d confidence intervals for posthoc/contrasts/marginal-means in an ANOVA. The np2/w only gives the overall differences between all conditions, but often times the most important effect of interest is the effect of the contrast between two effects. Sure, one could run a t-test and get that (alas, with no CIs, see comment below), but with 3 it's already 3 t-test to run, which gets even more complicated if you have an additional factor (two way ANOVA) or 4 or more conditions in a single factor, becoming a real chore. Simply adding d and d CIs to the existing tables would be terrific.
[I would also like to remind and reiterate the need for CIs for all effects reported (viewtopic.php?f=2&t=495). It's a shame to have to ask students to use online calculators to compute Cohen's d CIs outside of JAMOVI.]
Thanks,
Gilad