Hi
Thanks a lot for a prompt reply. In our case, one of the attributes is pretty lenghty. Merging it with the other one would create 50+ levels.
1. Wouldn't that introduce a lot of imbalance in the design?
2. Should there be a limit of e.g. 20 levels for the "merged" meta-attribute?
3. How would such merging impact relationships between original attribute levels? We'll be probably left only with the "interaction" components, but no main effect estimates.
To use your example of 3x3 + constraints=>8, will we still retain any info about level #1 of Attribute A, knowing (but not sharing it with CBC HB), that it is standing behing levels levels #1, #4 and #7 of the meta-attribute? If we lose the main effect estimates, is there a way to retrieve them from the 8 individual levels "post-hoc"?