One of my DOE users has defined a mixture design with 4 factors. To be more precise it is a mixture of mixtures.
During the tests it estimates 2 responses: pH and conductivity.
These two responses work as a couple. They do not necessarily want to define an optimal setting but couples of responses and therefore the optimal setting per couple.
I did a small example (with no constraints). Let's say that you have about an error of +/-0.01 for y1 and +/-0.02 for y2.
So, if you want to achieve (y1,y2)=(1.25,0.1), your limits are ([1.24, 1.26] & [0.08,0.12]) and you have the following design space:

let's change the couple (y1,y2)=(0.75,0.3)

and so on, you can do itcouple by couple, but if the number of couple isgrowing , does anyone have a way to do it efficiently?
Thank you for your suggestions,
Florence