Hi
apologies for the slow reply. What you're seeing is caused by using limits in plotting. You're computing the overall density, but then you're plotting it for only a small part of the overall domain, and that's reflected in the shape you're seeing
Stephane
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Search found 1024 matches
- 05 May 2024, 18:39
- Forum: Post-estimation analysis/use of results
- Topic: WTP distribution in preference space
- Replies: 3
- Views: 2055
- 05 May 2024, 12:10
- Forum: Model specification
- Topic: Include independent variables with missing values
- Replies: 4
- Views: 2418
Re: Include independent variables with missing values
Hi
in that case, you would have missing data for a dependent variable (indicator in hybrid choice), and you would skip those rows for that dependent variable only. See the 'rows' setting
Stephane
in that case, you would have missing data for a dependent variable (indicator in hybrid choice), and you would skip those rows for that dependent variable only. See the 'rows' setting
Stephane
- 05 May 2024, 12:07
- Forum: Model estimation
- Topic: Estimation of MNL and MMNL in WTP space issues
- Replies: 7
- Views: 3280
Re: Estimation of MNL and MMNL in WTP space issues
Apologies for the slow reply. it would be randcoeff[["b_price"]] = price_mu + price_mu * (unif_draws_a+unif_draws_b)/2 but I would advise against that distribution as the moments of WTP then do not exist. See Daly, A.J., Hess, S. & Train, K.E. (2012), Assuring finite moments for willin...
- 05 May 2024, 12:02
- Forum: Model specification
- Topic: Latent variables without demographic predictors?
- Replies: 1
- Views: 7
Re: Latent variables without demographic predictors?
Hi
yes, this is no problem.
It's not likely to be the cause for your issue. Can you show us the estimates?
Stephane
yes, this is no problem.
It's not likely to be the cause for your issue. Can you show us the estimates?
Stephane
- 05 May 2024, 12:00
- Forum: Model specification
- Topic: Latent Class Analysis with Nested Logit Model
- Replies: 8
- Views: 8493
Re: Latent Class Analysis with Nested Logit Model
Hi
apologies for the slow reply
yes, you could possibly do that
Stephane
apologies for the slow reply
yes, you could possibly do that
Stephane
- 05 May 2024, 11:51
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 121151
Re: Unconditionals
apologies for the slow reply. This is very code specific, can you provide your code and data outside the forum and we can investigate
- 05 May 2024, 11:44
- Forum: Post-estimation analysis/use of results
- Topic: Difference in Marginal rate of substitution between MNL and Mixed logit models
- Replies: 1
- Views: 19
Re: Difference in Marginal rate of substitution between MNL and Mixed logit models
Hi
apologies for the slow reply
yes, this difference looks a bit too large to explain. Did you also look at the medians to see if they are reasonable (though we would want the means of course).
You might want to consider other distributions too with shorter tails
Stephane
apologies for the slow reply
yes, this difference looks a bit too large to explain. Did you also look at the medians to see if they are reasonable (though we would want the means of course).
You might want to consider other distributions too with shorter tails
Stephane
- 05 May 2024, 11:38
- Forum: Model estimation
- Topic: Covairance cannot be estimated in HCM
- Replies: 1
- Views: 10
Re: Covairance cannot be estimated in HCM
Hi
apologies for the slow reply.
Can you be more specific? Did you wait until the process has finished?
Stephane
apologies for the slow reply.
Can you be more specific? Did you wait until the process has finished?
Stephane
- 05 May 2024, 11:37
- Forum: Examples (existing and requests for new ones)
- Topic: Extending the MNL example on mode choice to MMNL
- Replies: 1
- Views: 16
Re: Extending the MNL example on mode choice to MMNL
Hi apologies for the slow reply. Using your numbering: 1) Mixed logit for random taste heterogeneity is fine. For correlation, you would be better with a nested logit or CNL kernel inside your mixture. 2) yes 3) You should not use Halton draws in that case. Try MLHS or Sobol. In relation to the sing...
- 05 May 2024, 11:33
- Forum: Estimation results
- Topic: correlation between latent variables in hybrid model
- Replies: 3
- Views: 3624
Re: correlation between latent variables in hybrid model
Hi yes, you're finding correlation. If your model estimates fine and gives you a covariance matrix, then you likely do not face an identification issue. in relation to correlation between the alternatives, I would recommend that you consider a GEV kernel such as Nested Logit instead of MNL inside yo...