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
    2. 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 1002 matches

by stephanehess
05 Jun 2020, 20:56
Forum: Feature requests
Topic: Output conditionals after LC model
Replies: 1
Views: 9891

Re: Output conditionals after LC model

Hi Juergen

sure. We will add this as an output in time for the official release of v0.1.1

And yes, the order is the same as in the database

Stephane
by stephanehess
29 May 2020, 21:34
Forum: Errors during model validation and/or estimation.
Topic: ICVL Model Identification issues
Replies: 3
Views: 6278

Re: ICVL Model Identification issues

Sure,

but for the binary one, it would be easier for you to use apollo_mnl than apollo_ol

Best wishes

Stephane
by stephanehess
28 May 2020, 08:48
Forum: Examples (existing and requests for new ones)
Topic: Models with reaction time
Replies: 4
Views: 11381

Re: Models with reaction time

Hi Silvia

if an attribute is stochastic, whether as a function of reaction time or some other phenomenon, then you can code it in apollo_randCoeff - it makes no difference whether the components included in that list are random coefficients or random variables

Best wishes

Stephane
by stephanehess
27 May 2020, 23:18
Forum: Examples (existing and requests for new ones)
Topic: Models with reaction time
Replies: 4
Views: 11381

Re: Models with reaction time

Hi Silvia

this is a very specific application of a model. You could definitely code the model in Apollo but this would involve some manual coding of the model components and then using Apollo for the estimation

Best wishes

Stephane
by stephanehess
25 May 2020, 22:30
Forum: Errors during model validation and/or estimation.
Topic: ICVL Model Identification issues
Replies: 3
Views: 6278

Re: ICVL Model Identification issues

Hi it's of course difficult to diagnose the problem without access to the data, but this looks at first hand like an identification issue. The zeta parameter becomes very large for one indicator while the taus become very wide too. I noticed that you used a different specification for the structural...
by stephanehess
23 May 2020, 21:10
Forum: Model specification
Topic: How to choose random parameters for MMNL model
Replies: 3
Views: 5964

Re: How to choose random parameters for MMNL model

Hi Shan

yes, you should be able to make those parameters non-random where the standard deviations are not significant. Keep an eye on your model fit too to see if you're not losing fit by doing so

Best wishes

Stephane
by stephanehess
23 May 2020, 21:07
Forum: Post-estimation analysis/use of results
Topic: Estimating the average marginal effects of a mixed logit within Apollo's post-estimation functions?
Replies: 2
Views: 5462

Re: Estimating the average marginal effects of a mixed logit within Apollo's post-estimation functions?

Hi Brenna apollo_prediction makes use of the full distribution of the random coefficients. So it will take the estimated parameters and create draws for the coefficients at the person level, using the number of draws you specified in the settings for draws. It will then calculate the probabilities w...
by stephanehess
19 May 2020, 12:46
Forum: Model specification
Topic: Between subject design
Replies: 3
Views: 5890

Re: Between subject design

Dominik

I think what you need to do first is to analyse the choices in the two subsets. Your results are quite possibly driven by a situation where nobody in the private segment chooses option 6 or 8

Best wishes

Stephane
by stephanehess
18 May 2020, 14:12
Forum: Errors during model validation and/or estimation.
Topic: Error in Bayesian estimation
Replies: 6
Views: 9373

Re: Error in Bayesian estimation

Hi Jason this is a common issue that happens to people when using Bayesian estimation through RSGHB. The issue is that you ran the whole file in one go. RSGHB, which is used by Apollo for Bayesian estimation, asks you to confirm before continuing the estimation. As you ran the whole file in one go, ...