Hey Stephane,
thank you very much for your reply!
It works when I set all interactions for one alternative to zero.
Is it then still necassary, as I did in the example, to set one interaction for each alternative to zero too?
Pia
Important: Read this before posting to this forum
- 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.
- 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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- Check that the same issue has not already been addressed in the forum - there is a search tool.
- Ensure that the correct syntax has been used. For any function, detailed instructions are available directly in Apollo, e.g. by using ?apollo_mnl for apollo_mnl
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- Users can check which version they are running by entering packageVersion("apollo").
- Then check what is the latest full release (not development version) at http://www.ApolloChoiceModelling.com/code.html.
- To update to the latest official version, just enter install.packages("apollo"). To update to a development version, download the appropriate binary file from http://www.ApolloChoiceModelling.com/code.html, and install the package from file
- If the above steps do not resolve the issue, then users should follow these steps when posting a question:
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Search found 3 matches
- 26 Nov 2022, 10:39
- Forum: Errors during model validation and/or estimation.
- Topic: positive Hessian eigenvalues
- Replies: 3
- Views: 1388
- 19 Nov 2022, 17:24
- Forum: Errors during model validation and/or estimation.
- Topic: positive eigenvalues causing NaNs
- Replies: 1
- Views: 993
positive eigenvalues causing NaNs
Hey, I'm trying to calculate a model with categorical variables for precipitation. I fixed the asc for walking and the first class of precip for each mode. As soon as I get all my betas in, the s.e. and t.ratio produces NaNs. This is my code: ### Initialise code apollo_initialise() ### set core cont...
- 12 Nov 2022, 12:54
- Forum: Errors during model validation and/or estimation.
- Topic: positive Hessian eigenvalues
- Replies: 3
- Views: 1388
positive Hessian eigenvalues
Hey, I have some problems with the estimation, because I get positive eigenvalues, as soon as I use all of my betas. The more betas I add, the bigger becomes the eigenvalue to a point, where its 0 or positive and my model fails. I tried it with a subset of my data and checked on every beta, but as s...