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. We check the forum at least twice a week. It may thus take a couple of days for your post to appear and before we reply. There is no need to submit the post multiple times.
Search found 3 matches
- 05 Dec 2024, 14:31
- Forum: Estimation results
- Topic: Positive Price Coefficient
- Replies: 4
- Views: 50683
Re: Positive Price Coefficient
Perfect. Thanks for the clarification.
- 04 Dec 2024, 15:37
- Forum: Estimation results
- Topic: Positive Price Coefficient
- Replies: 4
- Views: 50683
Re: Positive Price Coefficient
Thanks for your response! Hoping you can clarify one point for me.
In my notes, I have written that when discussing the uncorrelated MMNL model in Apollo instructors said that "we don't necessarily expect the mean parameters to be negative because we are going to use a negative exponential around ...
In my notes, I have written that when discussing the uncorrelated MMNL model in Apollo instructors said that "we don't necessarily expect the mean parameters to be negative because we are going to use a negative exponential around ...
- 30 Oct 2024, 20:57
- Forum: Estimation results
- Topic: Positive Price Coefficient
- Replies: 4
- Views: 50683
Positive Price Coefficient
In this year's Choice Academy, instructors discussed that when price is distributed negative lognormal we may not expect the price coefficient to be negative in our mixed logit models (rather the sign and size are related to the level of price sensitivity). For example, when I run my mixed logit ...