Design for combined DCE and BWS

[Andrew]

Hi,

we would like to combine CBC and BWS Case 2 in one survey. In our study, we have 12 choice tasks with 2 alternatives each. After every choice task of we want to ask the respondents for the best and worst attribute level of the chosen alternative. Which design would be most suitable to analyze both exercises (e.g. on an aggregated basis)? Is there one design we can use for both exercises simultaneously; e.g. OMEP?

Kind regards,
Andrew

[Michiel Bliemer]

I have no experience with best-worst scaling (case 2), but I can imagine that you would like to have variety in attribute level combinations. Since you do not know which alternative which be chosen in advance, it is not possible to optimise for BSW case 2 in your study I suppose, but I expect that an orthogonal design (OMEP) would work fine since it provides a nice coverage of attribute levels and attribute level combinations.

Michiel

[Andrew]

Michiel,

thank you very much for the quick reply. We are more aware of the problems with our approch now and might adapt it a little bit.
Instead of using the chosen alternative in the cbc for the best-worst scaling exercise we might just take the first of the two alternatives (regardless of repondents choice). We could use the colums for the 1st alternative in the orthogonal design for the subsequent bws exercise. An orthogonal design might provide an adequate attribute level balance.

Regardless of the above-mentioned, does Ngene provide a syntax (now or in near future) to create designs for best-worst scaling? We use Ngene 1.1.2.

Kind regards,
Andrew

[Michiel Bliemer]

We have no intention to include designs for BW case 1 or 2 as this is very different type of analysis. But we do intend to include BW case 3.