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 9 matches
- 08 Apr 2022, 12:51
- Forum: Data
- Topic: Data set with missing values
- Replies: 7
- Views: 10420
Re: Data set with missing values
That's exactly how I deal with it. I just want to make sure it's the right way to do it. Thank you, Prof. Hess.
- 05 Apr 2022, 14:02
- Forum: Data
- Topic: Data set with missing values
- Replies: 7
- Views: 10420
Re: Data set with missing values
Dear Prof. Hess, This is my model specification, and you can check the attachment for the complete data format. V[['alt1']] = asc_1 + b_tt * cartime + b_pollution * carpollution V[['alt2']] = asc_2 + b_tt * prtime + b_fee * prfee + b_capacity_2 * capacity + b_comfort2_2 * comfort2 + b_comfort3_2 * c...
- 05 Apr 2022, 03:26
- Forum: Data
- Topic: Data set with missing values
- Replies: 7
- Views: 10420
Re: Data set with missing values
Hi, Prof. Hess, I am very sorry for not describing my problem clearly. For example, let's assume that each respondent is required to complete 18 (9+9) hypothetical scenarios. Scenario 1-9: including 8 attributes, and then 9 scenarios are obtained through uniform design. Scenario 10-18: including 10 ...
- 03 Apr 2022, 11:08
- Forum: Data
- Topic: Data set with missing values
- Replies: 7
- Views: 10420
Data set with missing values
Hello Prof. Hess, My data set inherently has missing values. I designed 9 SP scenarios with different variables between each 3 scenarios, but the alternatives are the same for all scenarios. For example, I considered 3 variables in Scenario 1-3, 2 additional variables in Scenario 4-6, and 3 addition...
- 08 Jul 2021, 10:56
- Forum: Post-estimation analysis/use of results
- Topic: MNL model- elasticity calculations
- Replies: 2
- Views: 4532
Re: MNL model- elasticity calculations
Dear Prof Hess,
Thank you very much for your quick reply!
Yue
Thank you very much for your quick reply!
Yue
- 08 Jul 2021, 08:03
- Forum: Post-estimation analysis/use of results
- Topic: MNL model- elasticity calculations
- Replies: 2
- Views: 4532
MNL model- elasticity calculations
Hi, prof Hess, I met a mistake when attempting to calculate the elasticity in the MNL model. Here is the warning: WARNING: Element database in the global environment differs from that inside apollo_inputs. The latter will be used. If you wish to use the former, stop this function by pressing the &qu...
- 01 May 2021, 16:40
- Forum: Model estimation
- Topic: A simple question related to ICLV model
- Replies: 3
- Views: 7154
Re: A simple question related to ICLV model
Thanks for the prompt reply prof Hess! I have solved the problem with your help. Another question is that after the estimation process, only the coefficients of the variables are given, and other results always being calculating. Could this be related to the hardware of the computer?
- 25 Apr 2021, 11:14
- Forum: Model estimation
- Topic: A simple question related to ICLV model
- Replies: 3
- Views: 7154
A simple question related to ICLV model
Hi, Prof. Hess, I encountered a problem in estimating the ICLV model. We all know that sometimes, not all values in attitudinal indicators are selected. For example, in my study, no one chooses 1 in the indicator variable “CA1”. Then, the model reported an error message: Some levels in "coding&...
- 08 Dec 2020, 12:13
- Forum: Model specification
- Topic: Mixed Logit Model with inter and intra individual heterogeneity
- Replies: 1
- Views: 3890
Mixed Logit Model with inter and intra individual heterogeneity
Dear sir or madam, I am using Apollo to analyze my data by applying a mixed logit model. The MMNL model in my study should deal with both the heterogeneity across individuals and the heterogeneity across repeated choices for the same individual (panel mixed logit model). However, i am a little confu...