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Interpretation of the Effects of a Logit-Output

Dear Sawtooth Community,

I have a question about the "effects" in the output of a CBCA logit analysis.

After reading and summarizing the literature on Logit, I understand these in general. However, I wonder how I interpret the effects. According to https://www.sawtoothsoftware.com/download/techpap/cbctech.pdf you have to exponentiate the effects for a comparison. Can I therefore assume that these are the logit coefficients that have already been multiplied by the independent variable?
If this is not so, I would be glad if someone could explain to me what the stated effects says.

Best regards,

asked Jun 30 by anonymous

1 Answer

0 votes
The effects are the CBC utilities.  They are NOT the raw logit coefficients - for a 4-level attribute there would be 3 coefficients in the model (because of the effects coding of the categorical attributes).  In showing 4 effects for a 4-level attribute we've taken the 3 logit coefficients and multiplied them by the attribute's coding scheme (so that you have one effect per attribute level, for categorical attributes).
answered Jul 1 by Keith Chrzan Platinum Sawtooth Software, Inc. (63,000 points)