topic Re: Why the confidence interval from conditional prediction profiler has an irregular shape? in Discussions

Why the confidence interval from conditional prediction profiler has an irregular shape?

YangHong — Fri, 09 Jun 2023 00:29:41 GMT

Hi all,

I would like to understand why the conditional prediction profiler from a mixed model has an irregular shape.

Here I attached a dataset with 1 responses, and you will see the irregular shape of the CIs in conditional prediction profiler from a mixed model.

Re: Why the confidence interval from conditional prediction profiler has an irregular shape?

statman — Mon, 01 Mar 2021 17:44:59 GMT

There is various information on profilers built into JMP (https://www.jmp.com/support/help/en/16.0/#page/jmp/profiler.shtml#)

Your model is not very good. Have you analyzed the residuals? There is evidence of non-constant variance and possibly multiple distribution of errors. If you try removing some the effects from your model, you can watch the changes to the Rsquare-Rsquare adjusted delta and residual plots and subsequently the confidence curves.

Re: Why the confidence interval from conditional prediction profiler has an irregular shape?

SDF1 — Mon, 01 Mar 2021 18:28:23 GMT

Hi @YangHong ,

I would also add that it is not that common to have a two-factor interaction be more important than a main effect. It certainly can happen, but if the DOE is designed to look at the right factors, the main effects will almost always show more importance than two-factor interactions, which is related the the concepts of effect hierarchy and effect heredity. You can read more about it here.