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Hi Michiel,

I was wondering if there is a possibilty of heteroskedasticity in mixed logit estimations that bias the results (I have a mixed logit with some random parameters and an error component for the panel effect)? And if yes, where could heteroskedasticity come from and is there anything I ...

Dear all,

I was wondering if it could be necessary to use stochastic variables instead of deterministic variables (for the attributes or covariates) in my Mixed Logit model/Latent Class model.
I did not find pretty much literature on this topic besides "Diaz et al, 2015, Accounting for stochastic ...

Hi Michiel,

thank you very much for your advice.
So generally speaking, the restrictions in a design do not per se cause a problem to estimate interactions between the restricted attributes/levels just in my case there seems to be an issue with the ninth interaction effect?!
And also generally ...

Hi,

I´ve used the following code to generate my design:

Design
;alts = alt1*, alt2*, SQ*
;rows = 14
;block = 2
;eff = (mnl,d)
;alg = mfederov
;require:
SQ.amount = 3, SQ.period = 3
;reject:
alt1.amount = 3 AND alt1.period = 3,
alt2.amount = 3 AND alt2.period = 3
;model:
U(alt1) = b1[-0.4862 ...

With regard to option 1:
Is it appropriate here to compute the WTP by calculating
mu_Attribute/fixed price parameter
or is it also necessary to use the distribution of the random attribute parameter instead of the mean and divide it by the fixed price parameter?

Your advice is highly appreciated ...

Okay, so if my cost coefficient is lognormally distributed and my other attributes are normally distributed, I can compute WTP according to papers mentioned in option 2?

Thank you very much for your valuable insights.

Regarding option 2:
You mean assuming the cost coefficient being e.g. lognormal distributed and the other attributes being normally distributed?

Best,
J.

Dear Michiel,

I have a question on the calculation of willingness to pay in mixed logit:

Is it appropriate to randomise the price attribute as well as the other two attributes of my experiment AND then use the random parameter averages to calculate the WTP (mu_Attribute/mu_price)?
I am not sure if ...

Hi Michiel,

thank you for your response. What you are writing is exactly what my code does. I will post it to the Apollo forum again to check for the code itself.
But thank you for commenting on the general idea. Very helpful!

Best,
J.

Hi Michiel,

I have a question on model specification:

I have a choice experiment with three attributes - A1(b_Beitr) with only numerical levels, A2 (b_HoeheEEE) and A3 (b_ZeitEEE) with three numerical levels plus one nominal level each.

In the first approach I have dummy coded A2 and A3 entirely ...