for HB results how to do two-way analysis of variance

Question

It is easy to do one-way analysis of variance with covariates for e.g. gender and university. However, how can I calculate if the interactions of gender and university  are significant.

Answer 1

Merjah,

ANOVA is something you'll need to run in your general purpose stat testing software (SAS, SPSS, etc.).

Comments

How do I make the different respondents utilities to be on the same scale. To make them to be of same length?

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You can use the ZCD transformed utilities instead of the raw utilities.  

If you need to do this calculation, it is described here:  https://sawtoothsoftware.com/forum/6140/is-there-a-formula-for-calculating-the-zero-centered-diffs

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Thank you! I am doing the two way analysis for a scientific journal article. I always before used covariates for one way analysis. In your forum that is suggested. How  "correct" is it to use traditional statistics for this?

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Oh, if you're using the analysis for a journal article, I would think you would want avoid traditional frequentest statistics, if that's what you've done in the past.  I'm not clear, though, on how you ran the analysis before with covariates.

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I have used covariates to do ANOVA, one-way analysis of variance following the technical paper of Sawtooth by Orme and Howell. The problem is that I have two categorical variables gender and university and I need to check also if there are significant interaction effects of gender and university. Absolutely routine in traditional statistics but not here . I wrote your support and they advised me to put a question here and possibly call Kenneth.

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I see the problem but I do not have a quick answer for you.  Contacting Kenneth is a good idea but I believe he is out of the office today.

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I would be very grateful for ideas how to do this. Thank you for this discussion. I have referred to a technical paper by you and Orme many times in articles.