Modeling and Multivariate Methods - SAS

Chapter 24 Visualizing, Optimizing, and Simulating Response Surfaces 581
Mixture Profiler
For an explanation of ternary plot axes for experiments with more than three mixture factors, see “More
than Three Mixture Factors” on page 581.
Figure 24.30 Explanation of p1 Axis.
p1 = 1
labels for
p1 axis
p1 axis
p1 = 0
More than Three Mixture Factors
The ternary plot can only show three factors at a time. If there are more than three factors in the model you
are profiling, the total of the three on-axis (displayed) factors is 1 minus the total of the off-axis
(non-displayed) factors. Also, the plot axes are scaled such that the maximum value a factor can attain is 1
minus the total for the off-axis factors.
For example Figure 24.31 shows the Mixture Profiler for an experiment with 5 factors. The Five Factor
Mixture.jmp data table is being used, with the Y1 Predicted column as the formula. The on-axis factors are
x1, x2 and x3, while x4 and x5 are off-axis. The value for x4 is 0.1 and the value for x5 is 0.2, for a total of
0.3. This means the sum of x1, x2 and x3 has to equal 1 – 0.3 = 0.7. In fact, their Current X values add to
0.7. Also, note that the maximum value for a plot axis is now 0.7, not 1.
If you change the value for either x4 or x5, then the values for x1, x2 and x3 change, keeping their relative
proportions, to accommodate the constraint that factor values sum to 1.