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  2. There is a very detailed manual for Apollo available at http://www.ApolloChoiceModelling.com/manual.html. This contains detailed descriptions of the various Apollo functions, and numerous examples are available at http://www.ApolloChoiceModelling.com/examples.html. In addition, help files are available for all functions, using e.g. ?apollo_mnl
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Search found 12 matches

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by Niranjan
18 Jan 2022, 09:09
Forum: Post-estimation analysis/use of results
Topic: Mean and SD of lognormal attribute correlated with another attribute
Replies: 4
Views: 3645

Re: Mean and SD of lognormal attribute correlated with another attribute

Thank you for clearing that out..
by Niranjan
17 Jan 2022, 12:15
Forum: Post-estimation analysis/use of results
Topic: Mean and SD of lognormal attribute correlated with another attribute
Replies: 4
Views: 3645

Re: Mean and SD of lognormal attribute correlated with another attribute

Thank you for the prompt reply,

One more thing
Does the correlation term s1_2 comes somewhere in the analytical formula?

I know generally we use mean= exp(m + s^2/2), but its the correlation parameter s1_2 that’s confusing me.
by Niranjan
17 Jan 2022, 10:07
Forum: Post-estimation analysis/use of results
Topic: Mean and SD of lognormal attribute correlated with another attribute
Replies: 4
Views: 3645

Mean and SD of lognormal attribute correlated with another attribute

Hi all, If I have two attributes of time: lognormally distributed and correlated as following: time1 <- -exp(m1 + s1 * draws1) time2 <- -exp(m2 + s2 * draws2 + s1_2 * draws1) Now if I want to find the mean and sd for the random variable time2 , is this the correct way of doing that? Find the uncondi...
by Niranjan
03 Aug 2021, 03:00
Forum: Data preparation, processing and pre-estimation analysis
Topic: Hybrid choice model structural part.
Replies: 1
Views: 5867

Hybrid choice model structural part.

Hello, everyone I have a very simple question on structural equation part of the hybrid model. While specifying the structural part of latent variable as random coefficients is it fine to just use the normal draws. For example I have interNormalDraws = c("eta") ## Now in random coefficient...
by Niranjan
16 Mar 2021, 23:29
Forum: Model specification
Topic: Elasticity with random parameter in mixed logit.
Replies: 6
Views: 8067

Re: Elasticity with random parameter in mixed logit.

Yes that does makes perfect sense. Thank you
by Niranjan
11 Mar 2021, 22:27
Forum: Model specification
Topic: Elasticity with random parameter in mixed logit.
Replies: 6
Views: 8067

Re: Elasticity with random parameter in mixed logit.

Thankyou for your valuable insights, i wanted to add a quick simple theoretical question (assuming the cost attribute is still normal), Does addition of the term to capture an income elasticity as mentioned by doing [([B_cost + sigma_cost * normal ) * (income)^B_inc] means we are changing the distri...
by Niranjan
05 Mar 2021, 00:36
Forum: Model specification
Topic: Elasticity with random parameter in mixed logit.
Replies: 6
Views: 8067

Elasticity with random parameter in mixed logit.

I have a question regarding the utility equation for understanding the elasticity in mixed logit model. I can think of two ways of including elasticity, suppose i have a utility equation with time and cost and income. 1) U = B_time * Travel time + [([B_cost + sigma_cost * normal ) * (income)^B_inc] ...
by Niranjan
24 Feb 2021, 20:21
Forum: Models and estimation
Topic: Best way to model directly correlated attributes.
Replies: 3
Views: 5864

Re: Best way to model directly correlated attributes.

Thank you for the swift response Dr. Hess, what do you mean by test the difference between parameters in last part?
by Niranjan
24 Feb 2021, 08:33
Forum: Models and estimation
Topic: Best way to model directly correlated attributes.
Replies: 3
Views: 5864

Best way to model directly correlated attributes.

Hello everyone, I am running a mixed logit model from unlabeled stated choice experiment with four attributes. I will try to explain in general a similar situation to my problem. 1) Attribute A 2) Attribute B 3) Cash back 4) Total Cost Now i can think of three ways to estimate the parameters a) Keep...
by Niranjan
06 Feb 2021, 22:50
Forum: Examples (existing and requests for new ones)
Topic: Hybrid choice modelling.
Replies: 4
Views: 9222

Re: Hybrid choice modelling.

Thankyou Dr Hess for the clearance,

I think my use of words were confusing, but your explanation makes it clear.

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