Define Custom Design

Click the Customize design button in the Define/Review Model dialog box to display the Define Custom Design dialog box. Use these options to select the specific effects that are to be included in the model and to specify whether factors and effects are random or fixed.

Grouping variables. The Grouping variables group box contains the grouping variables (factors) selected for the current analysis. Select the variables you want to include in the design. To designate a factor as fixed or random, select the variable in the Grouping variables group box, then click the Random or Fixed button in the Grouping variables group box.

Method. The Method group box contains the available options for including the selected variables as effects in the design. Some options may only be available if the appropriate number and types of variables were chosen in the Grouping variables group box. For a discussion of various designs (e.g., factorial, nested), see the Types of Analyses topic in the GLM - Introductory Overview.

Add. Click the Add button to add the main effects for the chosen factors to the list of Effects.

Full cross. Click the Full cross button to create the respective interaction term for all selected variables (e.g., Gender*Group*Time). Note that this button is only available if two or more variables are selected.

Full factorial. Click the Full factorial button to create a full factorial design for the selected grouping variables (e.g., Group Gender Time Group*Gender Group*Time Gender*Time Group*Gender*Time). Note that this button is only available if two or more grouping variables are selected.

Fact. to deg. Click the Fact. to deg. (Factorial to degree) button to create a factorial design (up to the degree specified in the Design degree field) for the selected factors (e.g., Group Gender Time Group*Gender Group*Time Gender*Time). Note that this button is only available if two or more grouping variables are selected.

Hierar. nest. Click the Hierar. nest (Hierarchical nesting) button to display the Nesting for Between-Group Factors dialog; in that dialog, specify the nested structure of the design for the selected factors. Note that this button is only available if two or more grouping variables are selected.

Design degree. Use the Design degree field in conjunction with the Fact. to deg. option; see above.

Effects. The group box shows the effects currently in the design. These effects can further be edited via the following options:

Cross. Click the Cross button to cross two effects currently selected in the Effects group box; e.g., if two effects A and B(C) are currently selected, then Cross will add the term A*B(C) to the effects in the design. If more or fewer than two effects are selected, this button is not available.

Nest. Click the Nest button to nest two effects currently selected in the Effects group box; e.g. if two effects A and B are currently selected, then Nest will (1) add the term B(A) (factor B is nested in factor A) to the effects in the model and (2) remove the B main effect from the effects in the model. If more or fewer than two effects are selected, this button is not available.

Remove. Click the Remove button to remove the selected effects from the Effects group box.

Clear all. Click the Clear all button to remove (clear) all effects from the Effects group box.

Note: Reordering effects. To reorder the effects in the Effects group box, first select them (e.g., click on the effect or list of effects), then move the mouse cursor to the desired location in the list, and when the mouse cursor changes to the insertion bar  , click the mouse button to move the selected effects.

Random. Click the Random button to designate the selected effect as a random effect.

Fixed. Click the Fixed button to designate the selected effect as a fixed effect. For more information on fixed and random effects, see the Introductory Overview.

OK. Click OK to accept the changes made to the design and return to the Define/Review Model dialog box.

Cancel. Click the Cancel button to return to the Define/Review Model dialog box without accepting any changes.