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Randomize Treatments Within Block

Hi SE Community,

Had a question from a customer on how to randomize all treatments within a block.

DOE has 2 discrete numeric factors with 3 levels. So there are 9 possible treatments. Customer wants to do 3 replicates of each treatment, so total of 27 runs.

They want the runs to be in 3 blocks - 9 runs per block. But for each block to contain all 9 treatments randomized.

Currently when doing the setup JMP will randomize the runs within the whole table. The issue this causes is that each block has repeat treatments at times (see image).

Does anyone know how to make it so each block has all possible treatments, but randomized within the blocks?

 

thank you!

 

 

Re: Randomize Treatments Within Block

OK. This is ugly but I think it should always work. A problem with using Custom Design is that you're not guaranteed of having all nine combinations. Use Full Factorial Design under DOE > Classical. Specify 2 Discrete Numeric factors and 2 Replicates. Leave Run Order Randomized.

Create the table. Add a column with the sequential row numbers (I've called it Run in the attached table).  Create a categorical column Block with this formula

 where X1 and X2 are your factors. Add it as a random factor to the model.

 Replace the Model table script with this. 

Would probably be a good idea to test this out to make sure it works for you and I didn't overlook anything.

 

Re: Randomize Treatments Within Block

Should have added to sort by Block when you're done so the runs are organized by block.

Re: Randomize Treatments Within Block

Maybe this is a Replicated Randomized Complete Block Design?

 

Re: Randomize Treatments Within Block

Yes, it is a replicated RCBD. It has two factors, though. BIBD only let's you have one.

Re: Randomize Treatments Within Block

This might be a bit of a hack, but:

1. DOE > Classical > Full Factorial
2. Add 2 3-level continuous factors
3. Click "Make Table" 3 times
4. Tables > Concatenate those 3 tables, checking the "Create source column" checkbox
5. Change Table name column to Block, maybe do some checking of numbering to be sure (Checksum column)

I think this results in what you want, but involves some extra steps. Table attached.

 

Re: Randomize Treatments Within Block

thanks Don, clever way to use the colrank formula....haven't done it like that before

Re: Randomize Treatments Within Block

Hi Jed,

this what I was thinking of doing as well....also never knew about checksum formula, thanks for that