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CBC design is deficient with Complete Enumeration and Balance Overlap but adequate with Shortcut

I have an alternative specific design that seems to be OK if I use the Shortcut method (i.e. all standard errors are under 0.05) but I get the deficient design warning every time I try to use Complete Enumeration or Balanced Overlap.

Why is this happening and how should I proceed?

Thanks in advance
asked Aug 1, 2017 by Anna

1 Answer

0 votes
When implementing alt-spec designs in CBC, all prohibitions used should completely X-out a row or completely X-out a column.  We do not recommend other types of prohibitions to be included also.  Do you have extra prohibitions that do not completely X-out a row or column?
answered Aug 2, 2017 by Bryan Orme Platinum Sawtooth Software, Inc. (175,315 points)
edited Aug 2, 2017 by Bryan Orme
Hello Bryan - and than you for your quick response.
No, all prohibitions I use completely cross out one or more levels of another attribute.
When I look at the Shortcut design report, the attribute that had asterisks in the Complete Enumeration report has a considerably lower efficiency. I suspect that this is because one level in this attribute has more alternative specific attributes (that would be shown with this level only) than the other level. However, when I look at standard errors for this attribute, they are actually very low and there is nothing in the advanced test report (for the design created using the Shortcut method) to suggest that the design is deficient.