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Connecting the utility report to the alpha file

Dear forum,

how do I connect the intercepts from the alpha file to the PWU in the utility report?
Shouldn´t be the mean of the used alpha draws be equal to the mean of the raw PWU (beta parameters) of the respondents in the sample?

asked Jul 2, 2019 by Chris Berlin Bronze (570 points)

1 Answer

0 votes
Back in the late 1990s when I first was learning HB, I also assumed that the average of the individual-level partworths should be equal to the alpha estimates.  They are not.  The alpha estimates are updated in each iteration based on the individual-level betas and the upper-level covariance matrix.  You will find that the average of the individual-level betas are very highly correlated with the alpha (population-level) part-worth estimates.  But, not exactly equal.
answered Jul 2, 2019 by Bryan Orme Platinum Sawtooth Software, Inc. (175,415 points)
Thanks Bryan, thinking like you in the LATE 1990 makes me proud. :-D