topic Re: No retrospective Parameter Power calculation available in Split-Plot analysis? in Discussions

No retrospective Parameter Power calculation available in Split-Plot analysis?

Jan — Thu, 08 Jun 2023 16:27:16 GMT

In the analysis of a typical DOE (using Standard Least Squares), there is a possibility to view the retrospective Parameter Power

(Estimates > Parameter Power).

However, when analysing a Split-Plot DOE (using REML), this option is not available.

I can imagine it is more complex to calculate, but would have expected it to be available somehow.

Re: No retrospective Parameter Power calculation available in Split-Plot analysis?

Mark_Bailey — Mon, 20 Mar 2023 15:25:18 GMT

JMP indeed provides a post hoc power analysis in some fitting platforms. JMP still includes it for historical reasons. It is considered today, though, an unhelpful, bad practice, or wrong to use. Here is one example of the pronouncements against using a retrospective power analysis. Many more can be found. Some ideas or practices fall out of favor over time after considerable thought and experience. In the meantime, it remains an expectation for some practitioners.