Allows you to specify which terms to include in the model. You must specify a hierarchical model.
· Crossed factors: if an interaction term is included, all lower order interactions and main effects that comprise the interaction term must appear in the model. For example, if the A and B interaction is included, denoted as A*B, then the A and B main effects terms must be included as well.
· Nested factors: if a nested factor is included in the model then the factor(s) in which they are nested must be included. If a factor is nested within multiple factors, the interaction terms between the parent factors must be included. You cannot include interaction terms for nested factors and their parents. For example, if C is nested in A and B, then A, B, and A*B must be included and A*C and B*C cannot be included.
Dialog box items
Include terms in the model up through order: Use this to quickly set up a model with a specified order. Enter the maximum order for terms to include in the model. For example, if you enter 2:
· All main effects and estimable two-way interactions display in Selected terms, and
· Minitab removes all estimable three-way and higher-order interactions from Selected terms and displays them in Available terms.
Available terms: Shows all terms that are estimable but not included in the fitted model.
Selected terms: Shows all terms that Minitab includes when it fits the model.