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
- Before asking a question on the forum, users are kindly requested to follow these steps:
- 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
- posts will not immediately appear on the forum, but will be checked by a moderator first. This may take a day or two at busy times. There is no need to submit the post multiple times.
Search found 10 matches
- 15 Dec 2023, 15:18
- Forum: Model specification
- Topic: probabilities of classes vary across choice tasks in a LC-MXL model
- Replies: 1
- Views: 36
probabilities of classes vary across choice tasks in a LC-MXL model
I am trying to develop a model testing for ANA (using a LC-Mixed Logit model) to avoid inflating the ANA. Given the high number of possible classes, I am using the methodology proposed by Hole, 2011. This gave me plausible results. From this model, I wanted to test the idea that attendance might var...
- 16 Jun 2023, 19:51
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 3842
Re: Log-uniform distribution (always positive)
Indeed, I haven't put enough thought on this, as this will make the distribution start at at 1
Thank you.
Thank you.
- 16 Jun 2023, 06:23
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 3842
Re: Log-uniform distribution (always positive)
Thank you for the clarification about the correlation. For the offset, I assumed that it was equal to zero, but I guess it is better to verify this!
Damien
Damien
- 09 Jun 2023, 13:08
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 3842
Log-uniform distribution (always positive)
In a WTP-space mixed logit model, I want to test a log-uniform distribution for the price attribute '(rationale: always positive and avoid long tail of log-normal); I have two questions (related code below) 1. Is the specification "exp(b_lambda * draws_lambda)" correct if I want a log-unif...
- 26 Apr 2023, 06:28
- Forum: Model specification
- Topic: Availability of alternatives different for each class in a LC model
- Replies: 4
- Views: 3329
Re: Availability of alternatives different for each class in a LC model
It now runs well including using multithreading. Thank you. Damien
- 25 Apr 2023, 14:28
- Forum: Model specification
- Topic: Availability of alternatives different for each class in a LC model
- Replies: 4
- Views: 3329
Re: Availability of alternatives different for each class in a LC model
Dear Prof Hess,
Just sent a sample data set on your gmail address and contact@apollochoicemodelling.com I hope this will reach you. Thank you.
Damien
Just sent a sample data set on your gmail address and contact@apollochoicemodelling.com I hope this will reach you. Thank you.
Damien
- 25 Apr 2023, 12:23
- Forum: Model specification
- Topic: Availability of alternatives different for each class in a LC model
- Replies: 4
- Views: 3329
Availability of alternatives different for each class in a LC model
I am trying to evaluate whether some heuristic akin to elimination by aspect is present in my data set. To do that, I wanted to develop a latent class, where the classes differ in the number of alternatives that are considered. I have modified the LC model in order to do that. I first, create a list...
- 26 Nov 2022, 07:38
- Forum: Model specification
- Topic: Latent Class BWS Model and Scale across classes
- Replies: 4
- Views: 1618
Re: Latent Class BWS Model and Scale across classes
Thank you for the clear answer. I'll read (again) your papers related to this topic.
Damien
Damien
- 26 Nov 2022, 04:30
- Forum: Model specification
- Topic: Latent Class BWS Model and Scale across classes
- Replies: 4
- Views: 1618
Re: Latent Class BWS Model and Scale across classes
Dear Prof Hess, Thank you for this clear reply, and the fact that I should consider the preference models as estimated separately (hence with potentially different scale factors). I understand that disentangling scale and preference parameters is difficult/impossible in many cases. To pursue on my q...
- 08 Nov 2022, 10:12
- Forum: Model specification
- Topic: Latent Class BWS Model and Scale across classes
- Replies: 4
- Views: 1618
Latent Class BWS Model and Scale across classes
Dear forum members, I have conducted a Profile (case 2) BWS survey. I am now estimating a latent class model with different scale factors for best and worst choices. I benefited from the examples and the previous discussions on this forum to run the model using Apollo. My question is more about the ...