Orthogonal Design Options
Minimum number of cases to generate. Specifies a minimum number of cases for the plan. Select a positive integer less than or equal to the total number of cases that can be formed from all possible combinations of the factor levels. If you do not explicitly specify the minimum number of cases to generate, the minimum number of cases necessary for the orthogonal plan is generated. If the Orthoplan procedure cannot generate at least the number of profiles requested for the minimum, it will generate the largest number it can that fits the specified factors and levels. Note that the design does not necessarily include exactly the number of specified cases but rather the smallest possible number of cases in the orthogonal design using this value as a minimum.
Holdout Cases. You can define holdout cases that are rated by subjects but are not included in the conjoint analysis.
- Number of holdout cases. Creates holdout cases in addition to the regular plan cases. Holdout cases are judged by the subjects but are not used when the Conjoint procedure estimates utilities. You can specify any positive integer less than or equal to the total number of cases that can be formed from all possible combinations of factor levels. Holdout cases are generated from another random plan, not the main-effects experimental plan. The holdout cases do not duplicate the experimental profiles or each other. By default, no holdout cases are produced.
- Randomly mix with other cases. Randomly mixes holdout cases with the experimental cases. When this option is deselected, holdout cases appear separately, following the experimental cases.
How To Set Options for an Orthogonal Design
This feature requires the Conjoint option.
- From the menus choose:
- In the Generate Orthogonal Design dialog, click Options.