Search found 3 matches

by Jacques
Thu Aug 25, 2022 7:12 pm
Forum: Help
Topic: Cohen's d for T test paired samples
Replies: 6
Views: 10016

Re: Cohen's d for T test paired samples

With my samples (48 observations) the two methods differ a lot in their results : d = 0.41 with Jamovi using d=(m1-m2)/SDdif d = 0.27 (Python pingouin) using d=(m1-m2)/pooledSD This is because the standard deviation of the differences is not the same as the pooled standard deviation of the two depen...
by Jacques
Thu Aug 25, 2022 11:59 am
Forum: Help
Topic: Cohen's d for T test paired samples
Replies: 6
Views: 10016

Re: Cohen's d for T test paired samples

Hi Magojam Thank you for your answer In https://github.com/jamovi/jmv/blob/master/R/ttestps.b.R#L66-L68 I see that d <- (m1-m2)/pooledSD #Cohen's d with pooledSD <- tryNaN(stats::sd(column1-column2)) but this is not the pooled SD, it the SD of the difference. Python pingouin.ttest uses for the denom...
by Jacques
Wed Aug 24, 2022 7:15 pm
Forum: Help
Topic: Cohen's d for T test paired samples
Replies: 6
Views: 10016

Cohen's d for T test paired samples

Hello. The Cohen's d effect size given by Jamovi (version 2.2.5.0) for T test for two paired samples is not the same as the one I calculate by hand (means dif/pooled_sd) or the one given by Python pingouin.ttest module. For T test for independent samples, the Conhen’s d given by Jamovi is the same a...