Dear Prof. Bierlaire,
I am sorry to bother you again.
After creating the utility functions for my mixed logit models, I am trying to calculate some indicators related to the cost parameter which is fixed. I have now two issues.
1. I followed your tutorial for the willingness to pay and I saw that we need to use the Derivate and then Estimate. Due to the fact that on the numerator I have a parameter that is normally distributed, how should I write the equation?
I was trying to use the Delta model (Reference: Chpater 5.2 of "Bliemer,
M.C.J., & Rose, J.M. (2013). Confidence Intervals of Willingness-to-Pay
for Random Coefficient Logit Models. Transportation Research Part B:
Methodological, 58, 199-214. https://doi.org/10.1016/j.trb.2013.09.010
.") and so incorporate it in the calculation in Biogeme:
Would you give me any hint how to decompose this equation in order to write in Biogeme?
2. Regarding the elasticities for the cost parameter (fixed) but from mixed logit model, I have great differences in the results between the generic and logit elasticity. Whats does it means? Which one is the most representative that I should choose?
I thank you in advanced for your help!
Louis Henri Furtado