i have several questions concerning my CBC:

1) I have price levels of 37.99, 30.99 and 24.99. I set them to be linear using a coding of 3.8, 3.1 and 2.5 is that correct?

2) If I run HB my price value is -142.8. What exactly does that stand for?

3) Now if I take a look at my interaction effects I get two different results in opposite directions: If I use linear price the effect of Attribute 1 level 1 and Attribute2 level 1 is positive. If I use price constraints or neither constraints nor linear pricing the effects of Attribute 1 level 1 and Attribute2 level 1 turns out to be negative. Is there an explanation for this? Am I doing something wrong?

4) I would like to analyse the WTP of my interaction effects. I know there are concerns about calculating WTP with CBC results still I would like to take a closer look into what effect the combination of two attribute levels has on the WTP. Is there a formula to do that?

Thanks in advance!

Thank you for your help!

Concerning your response to question 3: Is there a rule on how to choose to set the price to be linear? My ZC diff utilities for the price are linear could that be an indication?

I would like to run a regression analysis explaining the WTP for different attribute levels and interaction effects on the individual level. If I were to calculate the WTP with the not recommended formula would it be possible to calculate the interaction effects in the same way all other attribute levels are calculated?

Do I use the ZC diff value for the linear price as price coefficient? Or do I have to do something with it?

Thank you!