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 8 matches

by LauraThoWal
11 Jun 2021, 18:36
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

Ah, thank you! I really appreciate you taking the time to offer your advice. I expanded the code to include the other parameters such as "Trust" and "Equity". I get a warning message with the model results ("Some eigenvalues of Hessian are positive, indicating potential prob...
by LauraThoWal
10 Jun 2021, 18:42
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

Hi David, Thanks for the quick reply! For some broader context, I want to know what variables influence the decision to farm, scare, kill, or conserve (my 4 V utilities). This includes personal attributes like gender and experimental conditions like treatment. These variables would of course be cons...
by LauraThoWal
10 Jun 2021, 16:11
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

Thanks David! Storing as a dataframe rather than tibble sorted out the issue. I am a little confused about explanators vs utilities in Apollo though. My understanding is that explanators are socio-demographic attributes of participants, and the utilities are characteristics of the choices/tasks. How...
by LauraThoWal
06 May 2021, 10:57
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

Thanks for the suggestion David. I just downloaded the v0.2.5, but unfortunately still get the same error:

Code: Select all

Error in apollo_validateData(database, apollo_control, silent = TRUE) : 
  All rows for the same individual should be next to each other in the data!
by LauraThoWal
04 May 2021, 10:56
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

I am having the same problem. Has a solution/explanation been found?
by LauraThoWal
27 Apr 2021, 17:37
Forum: Errors during model validation and/or estimation.
Topic: Input validation code works on other PC, not mine
Replies: 16
Views: 47263

Re: Input validation code works on other PC, not mine

I am also getting the same error. I have ensured all the observations for the same individual are contiguous in the dataset, but am still getting: > apollo_choiceAnalysis(choiceAnalysis_settings, apollo_control, database) Error in apollo_validateData(database, apollo_control, silent = TRUE) : All ro...
by LauraThoWal
19 Apr 2021, 17:49
Forum: Data preparation, processing and pre-estimation analysis
Topic: Error code with choiceAnalysis_settings
Replies: 2
Views: 8493

Error code with choiceAnalysis_settings

I'm analysing RP data from two case studies, but am getting an error when it comes to "choiceAnalysis_settings". #### ANALYSIS OF CHOICES choiceAnalysis_settings <- list( alternatives = c(farm=0, scare=1, kill=2, conserve=3), avail = 1, choiceVar = moddata3$Choice, explanators = moddata3[,...