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Search found 6 matches

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by Mat2089119
13 Jun 2025, 15:14
Forum: Errors during model validation and/or estimation.
Topic: MMNL on SP/RP data - multiple cores error
Replies: 4
Views: 45423

Re: MMNL on SP/RP data - multiple cores error

Thanks for the quick reply. This seems to have been added when I was trying to debug the error with ChatGPT.

However, exactly the same error has happened before and is still happening when I remove this if statement. It also happens with a simple MNL version: 2 nodes produced errors; first error ...
by Mat2089119
12 Jun 2025, 12:03
Forum: Errors during model validation and/or estimation.
Topic: MMNL on SP/RP data - multiple cores error
Replies: 4
Views: 45423

MMNL on SP/RP data - multiple cores error

Hi,

I would like to estimate a mixed-logit from SP and RP data. The data comes from different RP/SP individuals, the SP data has 4 choice tasks for each individual, the RP data is just a single observation. I do not have the socio-demographics for the RP observations so they should only be used to ...
by Mat2089119
13 Jan 2025, 22:06
Forum: Model specification
Topic: Latent class model - preventing singular Hessian with a small parameter
Replies: 3
Views: 18861

Re: Latent class model - preventing singular Hessian with a small parameter

Thanks. Fixing the value does indeed allow to calculate the standard errors.
However, the model overall is quite unstable depending on the starting values. Is there a way to systematically optimize the starting values? (e.g. by trying 1,000 different combinations).
by Mat2089119
05 Jan 2025, 17:10
Forum: Model specification
Topic: Latent class model - preventing singular Hessian with a small parameter
Replies: 3
Views: 18861

Latent class model - preventing singular Hessian with a small parameter

Hi everyone,

I want to estimate a latent class model for a choice situation with 4 alternatives (alt4 being the output with u=0) and three classes.
I have adopted this example: https://www.apollochoicemodelling.com/files/examples/6%20Mixture%20models/LC_with_covariates.r
My dataset is relatively ...
by Mat2089119
06 Jun 2024, 10:38
Forum: Errors during model validation and/or estimation.
Topic: Error in inClassProb[[i]]$like * classProb[[i]]$like : non-conformable arrays
Replies: 3
Views: 12964

Error in inClassProb[[i]]$like * classProb[[i]]$like : non-conformable arrays

Hi,

I am trying to estimate a LC model with random parameters.
Without the random parameters, the exact same model specification works without a problem.

Unfortunately, I am getting the error:
Error in inClassProb[[i]]$like * classProb[[i]]$like :
non-conformable arrays

I saw similar errors ...
by Mat2089119
07 Mar 2024, 18:41
Forum: Examples (existing and requests for new ones)
Topic: Extending the MNL example on mode choice to MMNL
Replies: 1
Views: 11616

Extending the MNL example on mode choice to MMNL

Dear Professors,

I am currently learning choice modelling. As I will do a quite similar project, I have tried to expand the example on mode choice (with socio-demographics) to a Mixed-Logit model. I would greatly appreciate if you could answer a few conceptual questions whether I am on the right ...

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