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 11 matches
- 28 Sep 2022, 21:57
- Forum: Errors during model validation and/or estimation.
- Topic: Error: Error in paste0 ... result would exceed 2^31-1 bytes
- Replies: 3
- Views: 3589
Re: Error: Error in paste0 ... result would exceed 2^31-1 bytes
Hello David, I did a starting value search, and started with estimates from a previous model run with a larger data set. Those didn't give the error. The resulting estimates where nonsense, very large in absolute value. I updated apollo, and now it reports that the Hessian has some complex eigenvalu...
- 28 Sep 2022, 00:28
- Forum: Errors during model validation and/or estimation.
- Topic: Error: Error in paste0 ... result would exceed 2^31-1 bytes
- Replies: 3
- Views: 3589
Error: Error in paste0 ... result would exceed 2^31-1 bytes
Hello, I am estimating a number of mixed multinomial logit models on choice experiment data. Most of my models solve fine. However, one model run on a subset of the data fails. apollo_estimate iterates fine. It converges, and then proceeds through the parameter scaling and additional iterations. At ...
- 05 Jun 2021, 18:34
- Forum: Bug reports
- Topic: Error with Multi-threading model estimation
- Replies: 6
- Views: 18384
Re: Error with Multi-threading model estimation
I too have a problem with multithreading. Error in apollo_makeLogLike(apollo_beta, apollo_fixed, apollo_probabilities, : Model components are inconsistent across workers. Try seting apollo_control$nCores=1 This occurs when estimating a hybrid model with two latent variables, estimated using an order...
- 28 Jan 2021, 18:37
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
Thanks, particularly for your test code, which is what lead me to see what was going on.
John.
John.
- 28 Jan 2021, 03:47
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
Looking a bit further, the issue seems to be with my use of 'summary' instead of 'apollo_modelOutput'. Works fine when I use this to examine the results.
John.
John.
- 28 Jan 2021, 03:22
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
Thanks for the example. It works on my computer. However, the error still occurs with my data. To check on things, installed the latest version of R, updated apollo and all the other packages, and ran the analysis without loading any other packages. Also removed everything else from the database tha...
- 25 Jan 2021, 22:45
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
PS: I have been trying to use Apollo to reproduce a multivariate ordered probit, using a Choleski representation of the covariance matrix between the components. I am successful in running the model, but it chokes on generating the summary. I have set the bottom break points for the ordered probit t...
- 25 Jan 2021, 22:08
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
Hello David, Given that it took me till today to check the forum, no apology necessary for the belated response. And thanks for your reply. My tentative way forward is to use the R package 'mvord' to estimate a multivariate ordinal model of the choice among futures, and then use the predicted probab...
- 23 Dec 2020, 00:57
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
Hello Stephane, Thanks for reading my post, and apologies for the lack of clarity. I have attached a document setting out my current theoretical description of the modeling problem. I hope this is a bit more clear. After you look at the attachment, my question might be more clear. Specifically: I ha...
- 16 Dec 2020, 16:05
- Forum: Model specification
- Topic: Multivariate Ordered Logit Model
- Replies: 12
- Views: 16486
Re: Multivariate Ordered Logit Model
I've got a SP off RP style model that has a multivariate ordered RP component. It is an SP off RP style as the 'RP' component is survey participants choosing a future they believe the most likely from a set of possible futures, and then the subsequent SP experiment is pivoted off of that chosen futu...