Important: Read this before posting to this forum

  1. 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.
  2. 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
  3. Before asking a question on the forum, users are kindly requested to follow these steps:
    1. Check that the same issue has not already been addressed in the forum - there is a search tool.
    2. 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
    3. Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
    4. Make sure that R is using the latest official release of Apollo.
  4. If the above steps do not resolve the issue, then users should follow these steps when posting a question:
    1. provide full details on the issue, including the entire code and output, including any error messages
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Search found 5 matches

by TCEagle
03 Sep 2024, 18:17
Forum: Examples (existing and requests for new ones)
Topic: Bayesian estimation of a 2 level nested logit estimated using bayesian estimation
Replies: 2
Views: 48125

Bayesian estimation of a 2 level nested logit estimated using bayesian estimation

Dear team,

I am confused a bit on how to set up the apollo_probabilities function to fit a 2 level nested logit model using Bayesian estimation (through Apollo's call to RSGHB routines). In RSGHB we have to write out the logsum formulas and the nest probabilities and the within nest probabilities ...
by TCEagle
19 Jan 2021, 15:31
Forum: Model specification
Topic: MNL model using allocation data
Replies: 4
Views: 15246

Re: MNL model using allocation data

Awesome! Thank you David! That is a huge help. I had not thought to replicate the tasks and changing the choice.

Tom
by TCEagle
18 Jan 2021, 21:22
Forum: Model specification
Topic: MNL model using allocation data
Replies: 4
Views: 15246

Re: MNL model using allocation data

No, I think you misunderstood the issue. The allocation is at the individual respondent level. Think of a respondent allocating patients across a choice set of different treatments. The loglikelihood is the sum(allocation(j) * log(predicted Prob j)) where we sum across alternatives in the task ...
by TCEagle
15 Jan 2021, 01:13
Forum: Model specification
Topic: MNL model using allocation data
Replies: 4
Views: 15246

MNL model using allocation data

Does Apollo allow one to use proportions data from stated preference tasks in the MNL model?

I often have projects where I ask doctors to allocate a proportion of their patients across alternatives in the task. The log likelihood function becomes a simple weighted sum of the predicted ...