@JerryFish, Appreciate the slides and lecture you have provided for hypothesis testing.
One question I have is that t-test on JMP assumes we have unequal variance:
What if our samples are of equal variances, such us this male and female sample.
Would the pooled t test a better option?
Thanks.
Hi @carlogarcia ! Yes, a pooled t-test would be the better option if you can assume equal variances between the samples.
As you note, by default JMP assumes unequal variances. This results in wider confidence intervals (among other things) than for pooled variances, so it is a more conservative evaluation than a pooled t test.
But when you activate the "Means/ANOVA/Pooled t" from the red triangle, the results are indeed pooled.
Of course as you point out, you will want to have confidence that the two group variances are not different, and you get that through the red triangle "Unequal Variances" option.
Thanks for the comments!
Hello @JerryFish ,
How does one estimate the equivalence margin for an equivalence test?
I have a manufacturer who wants to expand manufacturing of a part to a new facility and I want to prove that the process pre move and post move are equivalent.
My initial thought was to use pre move data and derive the 90% confidence interval for std deviation and use a value within this range as my margin. But a value between 0.00488-0.007577 seems too small to conduct this study?
Any suggestions?
Thanks
Neha
