vs.

CBC, single profile with None and chip allocation

These two options seem approximately equivalent, if not exactly equivalent. Chip allocation with CVA does not require you to allocate chips to a none option like CBC does in these setups, but the mathematical implication is equivalent – you could essentially run this CVA design and add a none field post hoc and just fill it in with the remaining chips out of 100 – then run through CBC analysis. Is this true, that they are equivalent or is there some pro or con in terms of one being more robust way to generate utilities – because the datasets, are essentially the same, and reflects the same input thought process from respondents.

This then leads to the natural follow-up. If I am testing a design in CVA (again, with the setups I described above), CVA only provides me a test of the efficiencies which is interesting and somewhat informative, but it doesn’t take into account sample size or really give me a net target number to work towards. CBC, on the other hand, gives me reliabilities so I can see with my target of <.05, how good our design is and allow me to have more confidence in what tweaks are more beneficial. So my thought is to test the design with CBC but then implement it in CVA and run the analysis in CVA. I don’t want respondents to have to fill in a chip allocation for the profile and then unnecessarily fill in the sum to 100 in the none option (for CBC) – its an unnecessary additional step for them.

Does anything here sound off-base in my thinking of these CVA vs CBC designs?