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Utilities or ZC Diffs for simulator

I am building a simulator, and I usually use the raw utility scores when creating the simulator. I have received another simulator which the user has used Zero-Centered Diffs for their calculations.

Should I be using ZC Diffs or utilities when building a simulator and why?

asked Dec 8, 2017 by DaveT (245 points)

1 Answer

+1 vote

Use the raw utilities as they are the ones calibrated by the logit model you ran.  The ZCDs are transformed for reporting use and will NOT produce the proper shares in your simulator, under most circumstances.

ZCD would be OK if and only if the simulator was using only the "first choice" (AKA "maximum utility" or "winner takes all") rule for mapping utilities to choices.
answered Dec 8, 2017 by Keith Chrzan Platinum Sawtooth Software, Inc. (111,275 points)