Define Custom Mixture Design

Stat > DOE > Mixture > Define Custom Mixture Design

Complete the following steps to specify which columns are the factors in the design.

  1. In Components, enter the columns that contain the component data. Data must be in the form of amounts. When the mixture total is one, amounts and proportions are equivalent.
  2. In Process Variables (optional), enter any process variables you want to include in your design.
  3. Under Mixture Amount, select one of the following options:
    • Constant: Select if you only have one mixture total.
    • In Column: Select if you have more than one mixture total. Then, enter the column that contains the mixture amounts. Select this option when you have a mixture-amount experiment where the response is assumed to depend on the proportions of the components and the amount of the mixture. This option is not available if you specify a process variable.
  4. Click Lower/Upper. Minitab will not define the design before you review the lower and upper bounds of the components.

In this worksheet, Flavor is the response and contains the flavor scores. Emmenthaler, Gruyere, and Broth are the components. The values in these columns are the mixture proportions. In this design, the proportions in each row sum to 1. Temperature is a process variable.

The columns, Standard Order, Run Order, Point Type, and Blocks contain optional information that you can specify if the information is in the worksheet. If this information is not already in the worksheet, then Minitab creates these columns.

C1 C2 C3 C4 C5 C6 C7 C8 C9
Standard Order Run Order Point Type Blocks Emmenthaler Gruyere Broth Temperature Flavor
1 16 1 1 0.6000 0.0000 0.40 80 55
2 1 1 1 0.4000 0.0000 0.60 80 32
3 10 1 1 0.3000 0.3000 0.40 80 85
4 15 1 1 0.2000 0.2000 0.60 80 52
5 13 0 1 0.3750 0.1250 0.50 80 57
6 11 -1 1 0.4875 0.0625 0.45 80 56
7 2 -1 1 0.3875 0.0625 0.55 80 45
8 9 -1 1 0.3375 0.2125 0.45 80 71