Factors:

3 numeric factors

2 categoric factors

Goal:

I want to have a design where the values of my numeric factors always sum to a constant value (for example A+B+C = 100, where A, B, and C are continuous numeric factors). I also want to include 2 categoric factors.

Software:

Design Expert 13

Problem:

The mixture design is my go-to DOE design for keeping the sum of the values of numeric factors constant. Yet I can't find an option to add categoric factors to my mixture design.

And while it's easy to add categoric factors to an RSM design. I don't know how to modify the RSM design so that the sum of values for my numeric factors equals a constant.

I'd appreciate any solutions you have to offer.