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 21 matches
- 01 Jun 2022, 14:58
- Forum: Models and estimation
- Topic: Rho squared values for MNL models
- Replies: 1
- Views: 5195
Rho squared values for MNL models
Dear Concern, I tried looking into standard literature for the interpretation of the Rho squared. The search results report only the findings of Macfadden R square. Is there any threshold limit for Rho square? By including more parameters in my MNL model apart from the base MNL, rho square increases...
- 29 May 2022, 13:41
- Forum: Errors during model validation and/or estimation.
- Topic: Error in HCM model (NA in initial gradient value)
- Replies: 1
- Views: 1600
Error in HCM model (NA in initial gradient value)
Dear Concern, I get the following error while running HCM+Ol with 4 random components with the Halton draws of 500. Initially, I worked with Halton draws of 300 which easily converged. In this case, the model converged but I got this error. Any ideas to deal with such a problem? "Additional con...
- 20 May 2022, 06:09
- Forum: Errors during model validation and/or estimation.
- Topic: HCM with OL model estimation, Some levels in 'outcomeOrdered' do not exist in 'coding'
- Replies: 1
- Views: 1649
HCM with OL model estimation, Some levels in 'outcomeOrdered' do not exist in 'coding'
Dear Concern, I have 6 latent variables, in which the measurement indicators (likert scale 1-5) of the 2 latent variables are not answered (in some cases) by the respondents and as such, the CSV file has NaN'S field. I tried to fill them with 0. but the problem persists in the HCM model with OL says...
- 10 May 2022, 03:04
- Forum: Model estimation
- Topic: Interpretation for the Dummy coded (HCM model with OL)
- Replies: 1
- Views: 5287
Interpretation for the Dummy coded (HCM model with OL)
Dear Concern, With reference to the HCM model with the OL example, I have a question regarding the interpretation of the dummy coded variable. For example: in the example file, it is mentioned that, regular_user dummy variable for regular users > 1 for regular users, 0 otherwise university_educated ...
- 06 May 2022, 21:27
- Forum: Models and estimation
- Topic: HCM with Ordered Logit
- Replies: 1
- Views: 4101
HCM with Ordered Logit
Dear Concern, Citing the example of the HCM model with ordered logit, I have a question to ask: Lambda has been estimated while considering the starting value =1. Lambda has been multiplied with LV for the 2 alternatives (only for the branded products). My question is: 1. I am setting the HCM for an...
- 04 May 2022, 03:04
- Forum: Model estimation
- Topic: WTP calculation for MNL model
- Replies: 1
- Views: 4803
WTP calculation for MNL model
Dear Concern, I want to calculate the WTP from the MNL model. This MNL model is the base model. Going through the literature, I found out in calculating the WTP, which requires the ratio of the estimated coefficients. I have looked into the example of MNL model with SP covariates. I have not include...
- 30 Apr 2022, 21:31
- Forum: Post-estimation analysis/use of results
- Topic: Statistical Test for Restricted models
- Replies: 1
- Views: 1820
Statistical Test for Restricted models
Dear Concern,
Besides the likelihood ratio test (which is generally a test between the restricted and unrestricted model), What kind of test does Apollo do while comparing the two restricted models? Is there any script for the Wald test besides LR?
Besides the likelihood ratio test (which is generally a test between the restricted and unrestricted model), What kind of test does Apollo do while comparing the two restricted models? Is there any script for the Wald test besides LR?
- 29 Apr 2022, 01:14
- Forum: Errors during model validation and/or estimation.
- Topic: Estimation of Generic attribute design (SP survey)
- Replies: 4
- Views: 3366
Re: Estimation of Generic attribute design (SP survey)
Thank you so much SIr.
- 28 Apr 2022, 23:01
- Forum: Errors during model validation and/or estimation.
- Topic: Estimation of Generic attribute design (SP survey)
- Replies: 4
- Views: 3366
Re: Estimation of Generic attribute design (SP survey)
Thank you for the reply and help. I would like to know an additional thing. is it also possible to include the explanatory variables with the unlabelled MNL model? Such as the socio-demographics effect in an interaction term. If so, I tried using the following script to run the MNL model (unlabelled...
- 28 Apr 2022, 07:36
- Forum: Model specification
- Topic: Unlabeled experiment (MNL model with SP Covariates)
- Replies: 1
- Views: 1938
Unlabeled experiment (MNL model with SP Covariates)
Dear Sir, Q1. I am estimating an MNL model with SP covariates, generic alternatives, and only 4 attributes. Including 'ASC' in the utility function will help me to determine which of the alternative has been chosen/preferred to be chosen by the respondents mostly? While estimating, I see a small inf...