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 4 matches
- 30 Nov 2023, 14:29
- Forum: Errors during model validation and/or estimation.
- Topic: error "undefined columns selected"
- Replies: 2
- Views: 9347
Re: error "undefined columns selected"
Many thanks, that solves the problem!
- 31 Oct 2023, 15:02
- Forum: Errors during model validation and/or estimation.
- Topic: error "undefined columns selected"
- Replies: 2
- Views: 9347
error "undefined columns selected"
Hi, I have transformed the data for analyzing using the MDCEV model. I received the error Error in `[.data.frame`(database, , apollo_control$indivID) : undefined columns selected . Could you please help me to look at it? # Set working directory > setwd("..... ") > > # Initialise code > apo...
- 22 Jun 2023, 10:01
- Forum: Model specification
- Topic: Estimating MDCEV model with a price atrribute
- Replies: 2
- Views: 4136
Re: Estimating MDCEV model with a price atrribute
Oh that helps! Thank you very much!
- 21 Jun 2023, 15:43
- Forum: Model specification
- Topic: Estimating MDCEV model with a price atrribute
- Replies: 2
- Views: 4136
Estimating MDCEV model with a price atrribute
Dear developers, I wanted to estimate MDCEV model with my SP data where each choices also have a price attribute. I saw that in the Apollo manual, the sample data (time use data) for MDCEV does not include prices. As I understood, the base model of MDCEV assumes that there’s no price variation betwe...