How to code a split plot design in JMP Pro 15Hello,
I need advice on how to properly model a split-plot design in jmp pro 15. I think it needs to have random effects, so an LME model probably will work best I think?
I have three main effects: Temperature(Categorical), Cultivar(Categorical), Cultivar*Temperature.
Response Variable - (Continuous) Germination %
The experiment was conducted on (1)thermal gradient table. The cultivars were randomized in each subplot. (It is listed as 1-5 in order, but they are randomized at that level). The whole plot is the temperature. The split-plot would be the cultivars I believe. (See picture below for table layout.)
My model in jmp was going to look like this:
Fixed Effects:
Cultivar
Temperature
Cultivar*Temp
Random Effects:
Reps[Tempearture]
Does this account for the right error terms in jmp?
AnalyticsRe: How to code a split plot design in JMP Pro 15You should not include Rep in the model. It is automatically used to estimate the error variance. You need a new column called Whole Plot perhaps to indicate when the whole plot factor was reset. This variable will be used to estimate the whole plot variance while the Temperature variable will be used to estimate the fixed effects.
It looks like your design has Temperature as very hard to change and Cultivar as hard to change. That is, you did not randomize with one of these two factors. So you might want to select DOE > Custom Design and define these two factors this way. Select the option for nested levels to match what you did. This way will be easier, I think, than starting with a new JMP data table and creating all the data columns and meta-data to get the best analysis.
Re: How to code a split plot design in JMP Pro 15Great, thank you for taking the time to answer my question.
This is my first experience with JMP, so I'm not sure what all that means. I'll look through the website and see if I cant find some material to help me get there.
Thank you,
Michael
Re: How to code a split plot design in JMP Pro 15The JMP documentation is a good place to start. See the DOE Guide.
How did you make this design in the first place?
Re: How to code a split plot design in JMP Pro 15Great, I'll look into that. This is actually someone else's data. I was asked to analyze it. The experiment I'm designing is similar, but it will use 3 tables, not just one.
I see you have temperature as a continuous variable. Each temperature was fixed, I.e. temperature 1 = 130°c, 2 =°22 etc... so I've been coding them as categorical.
Many of my peers have split-plot designs too, so I've been trying to figure out how to do this in jmp for all our sakes.
-Michael
