Cohen's d with 95% CI

Valerie_Nedbal

Hi,

Is there a way how to get the Cohen's d with 95% Confidence intervals in JMP?

Thanks in advance,

Cheers,

Valerie

jiancao

Valerie,

JMP doesn’t report Cohen’s d. The effect size itself is relatively easy to calculate, but the confidence interval would need scripting. For example, Cohen’s d for two-sample mean difference is The components needed in the above formulas are readily available in the report from Fit Y by X.

To calculate the 95% CI the user needs to run the JSL Probability Functions, T Noncentrality (d, df, prob), to obtain two non-centrality parameters, nc_0.025 andnc_0.975, for the CIs. The 95% CI on d will be: d/(sqrt(1/n₁+1/n₂))* nc_0.025,  d/(sqrt(1/n₁+1/n₂))* nc_0.975.

Jian