It is possible that effects not included in your assumed model are active. In the Alias Terms outline, add potentially active effects that are not in your assumed model but might bias the estimates of model terms. Once you generate your design, the Alias Matrix outline appears under Design Evaluation. The Alias Matrix entries represent the degree of bias imparted to model parameters by the effects that you specified in the Alias Terms outline. For details, see the The Alias Matrix in Technical Details.
By default, the Alias Terms outline includes all two-way interaction effects that are not in your Model outline (with the exception of terms involving blocking factors). Add terms using the buttons. For a description of how to use these buttons to add effects to the Alias Terms table, see Model.
The Alias Terms table includes all two-way interactions by default. You can add the three-way interaction by selecting Interactions > 3rd.
Figure 3.22 Alias Terms Outline
Once you specify six runs in the Design Generation outline and click Make Design, the Design Evaluation outline appears. Open the Design Evaluation outline and the Alias Matrix outline. See Figure 3.23.
Figure 3.23 Alias Matrix