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  1. This forum is for questions related to the use of Apollo. We will answer some general choice modelling questions too, where appropriate, and time permitting. We cannot answer questions about how to estimate choice models with other software packages.
  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
  3. Before asking a question on the forum, users are kindly requested to follow these steps:
    1. Check that the same issue has not already been addressed in the forum - there is a search tool.
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    3. Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
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Search found 4 matches

by fsophie
20 Jun 2025, 15:36
Forum: Model specification
Topic: Error in LC MMNL
Replies: 7
Views: 48895

Re: Error in LC MMNL

Dear Stephane,

Thank you very much for your help, the model now runs without errors. However, it does not achieve estimation.

I tried to follow the suggestions from the FAQs and other blog posts, but have not found a solution. The MNL, MMNL and LC-MNL (with different numbers of classes) all run ...
by fsophie
29 May 2025, 10:38
Forum: Model specification
Topic: Error in LC MMNL
Replies: 7
Views: 48895

Re: Error in LC MMNL

Dear Stephane,

As I cannot share the data, I tried to simulate it, including non-attendance affecting two attributes. (Please note: in the final model, all attribute levels will be dummy-coded.)


# ################################################################# #
# ### LC-MMNL - using ...
by fsophie
28 May 2025, 17:44
Forum: Model specification
Topic: Error in LC MMNL
Replies: 7
Views: 48895

Re: Error in LC MMNL

Dear Stephane,

Thank you very much for your timely response.

I updated the code accordingly, but encountered the same error message. Overall, I am doubting if this model specification is equivalent to your LC-MMNL in your 2012 paper - inferring attribute non-attendance with the latent classes ...
by fsophie
28 May 2025, 12:31
Forum: Model specification
Topic: Error in LC MMNL
Replies: 7
Views: 48895

Error in LC MMNL

Dear Stephane and Apollo team,

I am trying to construct a Latent Class Mixed Multinomial Model following your 2012 paper for data that stems from a DCE. The experiment has two unlabeled alternatives and 6 attributes. However, I have been running into an error and cannot figure out how to solve it ...