The Space Filling mixture design type spreads design points fairly uniformly throughout the design region. It accommodates linear constraints. The design is generated in a fashion similar to the Fast Flexible Filling design method found under DOE > Space Filling Design (Fast Flexible Filling Designs).
For the Fast Flexible Filling mixture design type, enables you to select between the MaxPro criterion (the default) and the Centroid criterion. See FFF Optimality Criterion.
For the Fast Flexible Filling mixture design type, enables you to specify the average number of randomly generated points used to define each cluster or, equivalently, each design point. See Set Average Cluster Size.
The final design points can be obtained by using the default MaxPro (maximum projection) optimality criterion or by selecting the Centroid criterion. You can find these options under FFF Optimality Criterion in the report’s red triangle menu.
For p factors and n equal to the specified Number of Runs, the MaxPro criterion strives to find points in the clusters that minimize the following criterion:
Note: You can set a preference to always use a given optimality criterion. Select File > Preferences > Platforms > DOE. Select FFF Optimality Criterion and select your preferred criterion.
Note: Depending on the number of factors and the specified value for Runs, you might want to increase the average number of initial points per design point by selecting Advanced Options > Set Average Cluster Size.
The design region can be restricted by selecting the Linear Constraint option in the Linear Constraints outline.
1.

Select DOE > Mixture Design.

3.

Click Continue.

4.

Add Linear Constraints, if you have any.

5.

Specify the number of runs you want in the Runs box to the right of the Space Filling button in the Mixture Design Type dialog (Mixture Design Selection Dialog).

6.

Click Space Filling.

Consider a threefactor mixture design with the single linear constraint: . Space Filling Design with One Linear Constraint shows a ternary plot for a 30run Space Filling design that satisfies this constraint. (For a discussion of ternary plots, see Creating Ternary Plots.) Note that the points fall in the constrained design region and are fairly well spread throughout this region.