Hi @jlynn21,
@PatrickGiuliano already informed you about the current status of the platform and its options.
Choice designs may be seen as a specific subset of Fractional Factorial Design, with only categorical factors, a blocking/grouping of experiments (to create choice sets), a discrete choice response and often some constraints (for example the number of factors/attributes that can change in a subset of experiments/choice set).
Regarding your situation, I think there might be still two options to consider to help you (that can be combined):
- Use the Custom Designs platform, and based on the information you already have about your prior study, either use an A-Optimality criterion with A- Optimality Parameter Weights, to place more weight on the effects you want to reduce the variance. You can also specify directly in the Custom design platform the disallowed combinations (through filtering or scripting). Adding a random block can help creating the choice sets with the desired size.
- If you already have an existing prior study/choice design, use this design and use the Augment Designs platform. This way, the information from your previous design is kept, and the augmentation will help estimate more precisely the effects (with a D- or A-Optimality criterion, and possibility to add A-Optimality Parameter weights).
Hope this workaround can help you,
Victor GUILLER
"It is not unusual for a well-designed experiment to analyze itself" (Box, Hunter and Hunter)