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. We check the forum at least twice a week. It may thus take a couple of days for your post to appear and before we reply. There is no need to submit the post multiple times.

Search found 2 matches

by chtoune_63
21 Nov 2024, 20:31
Forum: Model estimation
Topic: Specify min / max for a parameter + power specification
Replies: 1
Views: 27914

Specify min / max for a parameter + power specification

Hi everyone,
Is it possible to restrict the values of a parameter to be estimated in a range? Ie to specify min and max values?
I'm asking this question because I get trouble with the estimation of a model with a power function.

My model is as follows:

U1=ASC1+alpha_cost*COST1+alpha1_time ...
by chtoune_63
28 Jun 2021, 17:03
Forum: Data preparation, processing and pre-estimation analysis
Topic: ChoiceVar
Replies: 3
Views: 43829

ChoiceVar

Hey,
I'm working on a very simple dataset to test Apollo. I get the following error message:

Error in apollo_preprocess(inputs = mnl_settings, modelType, functionality, :
The "choiceVar" argument for model component "model" needs to be a scalar or a vector with one entry per observation in the ...