topic Re: What Test Does JMP Run for Mixed Models in Discussions

What Test Does JMP Run for Mixed Models

SaltyScientist — Fri, 04 Jul 2025 14:01:57 GMT

I am trying to run stats in JMP and R, but my results tend to be different (wildly) when running the same datasets. Can someone describe the typical type of Type III ANOVA and associated multiple comp tests run when I select mixed model? How about for linear mixed? This is what I see when I ask chat gpt (I always take these with a grain of salt), any help is greatly appreciated!

Re: What Test Does JMP Run for Mixed Models

jthi — Fri, 04 Jul 2025 17:11:57 GMT

Have you looked for the information from JMP Help?

Re: What Test Does JMP Run for Mixed Models

MRB3855 — Sat, 05 Jul 2025 08:43:48 GMT

Hi @SaltyScientist . This may or may not be helpful, and I’m no R expert. But I do know that often “wildly” different results between R and SAS/JMP stems from not properly specifying the model; I.e., you have to be very careful with the syntax to make sure you are running the same model in R as you are in SAS/JMP. There are loads of articles about R vs SAS that may be helpful, and here is a link to one of them that also compares with JMP.

https://cscu.cornell.edu/wp-content/uploads/mixedmodelspec.pdf