Interpretation of ML and MNL models

[Ardeshir kohandel shirazi]

Dear Prof. Bierlaire,

My name is Ardeshir and I have a master’s degree in traffic and transportation engineering.  I have to admit that I am new and I don’t have a lot of information and experience in choice models. Right now I am working on a paper to study the heterogeneity in my statistical sample. My study has two alternatives (Pat and car) and I have used the MNL and mixed logit models to study the heterogeneity. The 5 images attached to this email illustrate the outputs of ML (by NLOGIT) and MNL (by Python) models. I have 4 questions that I have mentioned below and I would be truly thankful to have your help and guidance:

1-      What interpretations can I have from the output of my two models separately?

2-      How can I find the mathematical procedure (formula) of heterogeneity by MNL and ML models in order to write them down in the method section of my paper?

3-       How can I know that my overall model is statically significant by P-value and chi-squared?

4-      Can I say that those parameters which have an unexpected sign are not statically significant? (as an example the value of heterogeneity for in-vehicle time x job trip purpose has a positive sign)

Best regards