Mixture Design Tutorials - Statease.info

of your mixture components, the program will adjust the lower limit. In any case,
Design-Expert will help you build rational constraints.
Click on Continue to further specify the design.
Now you must choose the order of the model that you expect to be appropriate for the
system being studied. By default, Design-Expert uses Scheffe polynomials as mixture
models. In this case, you can assume that a quadratic polynomial, which includes
second order terms for curvature, will adequately model the responses. Leave the
default at Quadratic.
Simplex-Lattice Design Form
Via the following fields, Design-Expert provides options to strengthen the core simplex
design:
• “Augment design,” checked (�) by default, adds the overall centroid and
axial check blends to the design points.
• “Number of runs to replicate,” defaulted to 4, causes the specified number of
highest leverage experiments to be duplicated.
Accept these defaults by pressing Continue to the next step in the design process.
For Responses, select 2. Then enter the response Names and Units as shown
below.
Response Names and Units
You can step Back through the design forms and change what you want anywhere along
the way. When you press Continue on this page, Design-Expert will complete the
design setup for you.
7-4 • Mixture Design Tutorials Design-Expert 6 User’s Guide