cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Choose Language Hide Translation Bar
JMPdiscoverer
Level III

Can JMP generate a model without center-point runs?

Hello, 

I need your support for the following question. 

For a sake of time, we have performed a central composite design (2 factors, 5 levels, 2 responses one to maximize and one to keep lower than an upper limit, 40 runs) using a laboratory model (model 1) to identify our factors ranges.

In the meanwhile, a qualified laboratory model (model 2) was ready to perform additional runs, so, we performed confirmatory runs for those proposed ranges (9-10 runs) using model 1 instead of model 2. We identified an offset between the 2 models and model 2 is better presenting production. 

 

Could we use the 9-10 runs that we have with model 2 for a separate DoE analysis (mainly do some simulation experiments to predict the failure in the edges ?)  However, rather than doing runs in the center of each range, the “set point runs” need to be skewed to the lower left-hand region of the factor ranges. Can JMP accommodate this and give us (for example) predictions for failure rates at each corner of the ranges using model 2 ?

 

Thanks a lot for your support!

 

Best,

I

1 REPLY 1

Re: Can JMP generate a model without center-point runs?

The original DOE (central composite design) supported fitting a complex model (linear predictor) with first-order, second-order, and interaction effects. (Note that there are other design methods that result in other designs that would also support this model.) Using only the confirmatory to fit the same model might pose regression problems. The confirmatory runs are not necessarily sufficient to support fitting such a model well or at all.

 

Can you share the two data sets as JMP tables? Can make the data anonymous?