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 19 matches
- 18 Nov 2021, 13:19
- Forum: Model specification
- Topic: Mixed NL and CNL
- Replies: 2
- Views: 2917
Mixed NL and CNL
Dear Prof Hess With reference to your paper titled, " A joint model for vehicle type and fuel type choice: evidence from a cross-nested logit study ", I am also trying to estimate a mixed NL and CNL model. But regarding the random specification part, I have certain doubts. i) For the mixed...
- 22 Oct 2021, 13:25
- Forum: Post-estimation analysis/use of results
- Topic: Calculating logsum from the estimated model
- Replies: 1
- Views: 2888
Calculating logsum from the estimated model
Hi Prof Hess/ Prof Palma
While estimating a nested logit with 4 nests, I get 3 log sum parameters. Two values are below 1 while one is above 2.
So is the output normalized and it should come between 0 and 1 or is it 1/(log sum Parameter).
While estimating a nested logit with 4 nests, I get 3 log sum parameters. Two values are below 1 while one is above 2.
So is the output normalized and it should come between 0 and 1 or is it 1/(log sum Parameter).
- 27 Jul 2021, 19:03
- Forum: Bug reports
- Topic: Error with Multi-threading model estimation
- Replies: 6
- Views: 18660
Re: Error with Multi-threading model estimation
Hi Prof David I also get the same error message while estimating a nested ICLV model using multiple cores. This is what it shows - Error in apollo_makeLogLike(apollo_beta, apollo_fixed, apollo_probabilities, : Model components are inconsistent across workers. Try seting apollo_control$nCores=1 The m...
- 26 Jul 2021, 21:41
- Forum: Model estimation
- Topic: Multiple Cores for Nested ICLV
- Replies: 1
- Views: 4592
Multiple Cores for Nested ICLV
Hello Prof. Hess, Based on your example 24, I tried to estimate my own nested ICLV model. I get the following error while using multiple cores. Error in apollo_makeLogLike(apollo_beta, apollo_fixed, apollo_probabilities, : Model components are inconsistent across workers. Try seting apollo_control$n...
- 17 Jul 2021, 20:09
- Forum: Model specification
- Topic: Nested Logit Model
- Replies: 6
- Views: 6360
Re: Nested Logit Model
Thanks, Prof Hess. Based on the nested logit model, I have more of a conceptual doubt. My doubt is if a household uses a two-wheeler in the morning for maintenance purpose for home-based tour, and again they use app-based taxi like UBER, LYFT in the evening for same activity purpose. How to code the...
- 12 Jul 2021, 16:47
- Forum: Model specification
- Topic: Nested Logit Model
- Replies: 6
- Views: 6360
Re: Nested Logit Model
Thanks for the clarification.
- 11 Jul 2021, 20:41
- Forum: Model specification
- Topic: Nested Logit Model
- Replies: 6
- Views: 6360
Re: Nested Logit Model
It's the same as the example provided in Apollo Manual for two-level nested logit. Anyway here is the code. ### Clear memory rm(list = ls()) ### Load Apollo library library(apollo) ### Initialise code apollo_initialise() ### Set core controls apollo_control = list( modelName ="Apollo_example_4&...
- 10 Jul 2021, 17:14
- Forum: Model specification
- Topic: Nested Logit Model
- Replies: 6
- Views: 6360
Nested Logit Model
Hello Prof. Hess, Based on Apollo example 4, I just wanted to check if I want to specify a two-level nested logit model with slow_commute and fast_commute at the first level and 'car & bus' (slow) and 'air & rail' (fast) at the second level, whether the following specification is correct or ...
- 09 May 2020, 08:38
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16498
Multivariate Ordered Logit Model
Hi Prof. Hess, I have the following doubts on which I need your help. 1. Below attached is the code and output of the Multi-variate Ordered Logit Model. Is the model specification and output correct? 2. How does apollo_combineModels work ?? Can you please explain in brief and please suggest some pap...