Best simulation method for an Alternative Specific Design CBC

Question

Hi all - I did an Alternative-Specific Design in CBC, and ran it through CBC/HB.  SMRT doesn't seem to allow Randomized First Choice as the simulation method.  Would Share of Preference be my next best bet?  It is not a line extension exercise, so I do not anticipate having an IIA problem.

Second part of my question - can model tuning to holdouts via changing the exponent proceed for Share of Preference in the same manner it does for RFC?

Thanks, Nico

Answer 1

SMRT's RFC routine indeed cannot handle alternative-specific designs.  We figured out how to make it work in our newest Online Market Simulator.

That said, if you have individual-level utilities (via HB, for example), the Share of Preference (logit) simulation method should work fine, and I'd recommend you use it if you need to stick with SMRT for this project.

The tuning of the scale factor indeed works very similarly as with RFC.  Adjust the Exponent to make the shares steeper, relatively, or flatter.