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- 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
- Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
- Make sure that R is using the latest official release of Apollo.
- 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:
- provide full details on the issue, including the entire code and output, including any error messages
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Search found 6 matches
- 12 Sep 2025, 13:38
- Forum: Estimation results
- Topic: LC - positive (close to zero) cost coefficient in one class
- Replies: 5
- Views: 630
Re: LC - positive (close to zero) cost coefficient in one class
Thank you Stephan for looking into this, much appreciated. If LC has a better fit as you write, I'm now a bit uncertain how to interpret the conflicting results, or explain what is causing the large difference in WTP estimates, and which WTP estimates I should trust more. Would be grateful for any ...
- 09 Sep 2025, 11:51
- Forum: Estimation results
- Topic: LC - positive (close to zero) cost coefficient in one class
- Replies: 5
- Views: 630
Re: LC - positive (close to zero) cost coefficient in one class
Hi Stephan,
Yes, I have. With 0 initial values, it gives slightly different coefficients, but not too far from where I applied some random values (informed by MNL). When I used another set of different initial values, it still converged to the same model I copied in before.
Here are the model fits ...
Yes, I have. With 0 initial values, it gives slightly different coefficients, but not too far from where I applied some random values (informed by MNL). When I used another set of different initial values, it still converged to the same model I copied in before.
Here are the model fits ...
- 05 Sep 2025, 12:28
- Forum: Estimation results
- Topic: LC - positive (close to zero) cost coefficient in one class
- Replies: 5
- Views: 630
LC - positive (close to zero) cost coefficient in one class
Dear Apollo team,
I am trying to estimate a LC model for my choice data. Respondents had to choose from 2 options (Robot A and Robot B), attributes were: size (small, medium*, large), appearance(human, robot*, animal), function (func1*, func2, func3, func4), surveillance (yes/no), emergency call ...
I am trying to estimate a LC model for my choice data. Respondents had to choose from 2 options (Robot A and Robot B), attributes were: size (small, medium*, large), appearance(human, robot*, animal), function (func1*, func2, func3, func4), surveillance (yes/no), emergency call ...
- 26 Mar 2025, 14:09
- Forum: Estimation results
- Topic: Odds ratios
- Replies: 1
- Views: 4169
Odds ratios
Dear all,
Thanks for your support with Apollo. Can I please double check with you if I can convert estimated MNL coefficients to odds ratios simply by exponentiating the coefficients. Clinical audience would like to see odds ratios when I am presenting the model to them.
Many thanks,
Petra
Thanks for your support with Apollo. Can I please double check with you if I can convert estimated MNL coefficients to odds ratios simply by exponentiating the coefficients. Clinical audience would like to see odds ratios when I am presenting the model to them.
Many thanks,
Petra
- 22 Oct 2024, 14:34
- Forum: Estimation results
- Topic: comparing WTP estimates from MNL and MMNL model
- Replies: 2
- Views: 9257
Re: comparing WTP estimates from MNL and MMNL model
Thanks very much for the suggestions, David. This is very helpful. I have already included some interactions to the MNL model, which seems to work well. I will try to include more random coeff in the MMNL as well to see what happens.
Many thanks,
Petra
Many thanks,
Petra
- 18 Oct 2024, 14:19
- Forum: Estimation results
- Topic: comparing WTP estimates from MNL and MMNL model
- Replies: 2
- Views: 9257
comparing WTP estimates from MNL and MMNL model
Hi Stephan,
I am doing a DCE exploring willingness to pay for robots used in informal care. My attributes are 1) type (robot, human, animal); 2) size (small, medium, large); 3) function (func1, func2, func3, func4); 4) surv (0,1) 5) help(0,1); 6) cost (0,50,100,150)
I cannot figure out why my WTP ...
I am doing a DCE exploring willingness to pay for robots used in informal care. My attributes are 1) type (robot, human, animal); 2) size (small, medium, large); 3) function (func1, func2, func3, func4); 4) surv (0,1) 5) help(0,1); 6) cost (0,50,100,150)
I cannot figure out why my WTP ...