As part of my research I am running into a small issue regarding stated choice experimental design and would appreciate your input on the matter. I noticed a similar forum post ("Second choice with some NEW attributes") although I am unsure if the same responses hold for my context.
Context:
- Research is being done on transportation choices
Using Ngene to generate the design, have not run pilot test yet although priors are established in literature
Three alternatives: (alt1,alt2,alt3)
Three attributes, all continuous: (cost,time,distance)
One moderator: (air quality) [low,med,high] -> [0,1,2]
Problem:
If I want to measure the influence of the moderator on the beta of each attribute (i.e. does distance become more relevant?), should I create two models on Ngene (one with the moderator (four attributes) and one without (three attributes)) and make comparisons between the two or would it possible through one model?
Thanks for your time and any input is greatly appreciated.