Power_80_20 [Power / Sample Size]

posted by mittyri – Russia, 2019-01-04 00:24  – Posting: # 19726
Views: 1,384

Hi,

» In the results it is also evident that the post-hoc statistical power (power_TOST) is less than 80%, this is because the estimated point is greater than 105%, considering that the sample size was estimated expecting a difference less than / equal to 5%.

There are 3 basic factors in power calc: sample size, CV and PE. In post-hoc analysis sample size is fixed, but do not forget about CV! So the conclusion is valid if CV is equal or less than expected

» However, the statistical power of the ANOVA (Power_80_20) supports that the sample size used in the study was adequate, since the values ​​are greater than 90%.

:-D I think it should go to the trash bin. That's a conclusion based on WNL output, right?
See this old thread
That 'magick power' is not a power of ANOVA (whenever it could be) but the result of equality test using delta = 20%. That test has much more power than PowerTOST, thus, the value is higher than the previous one.
You cannot assess the sample size using that test.

Kind regards,
Mittyri

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