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.
  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.

Error in apollo_choiceAnalysis_settings

Ask questions about data format and processing of data, including the use of pre-estimation functions in Apollo. If your question relates to a specific error you are getting, please provide some of the output.
Post Reply
calgary
Posts: 1
Joined: 30 Jul 2021, 23:50

Error in apollo_choiceAnalysis_settings

Post by calgary » 31 Jul 2021, 00:20

Hello, I am new in using apollo. For testing and training I used the code of the homepage and there the first example (http://www.apollochoicemodelling.com/fi ... xample_1.r). I have a problem with the apollo_choiceAnalysis. Using the code and the dataset offered, I got no problems. But using the same code and change just a small bit to my personal dataset, I got a problem at the choiceAnalysis_settings with "rows".
I just want to analyse my variable "ppos" which has a value of 0,1,2 or 3. If I determine the rows setting to rows = database$ppos <4 ; all is working fine and I can do have a look to the output (also when I completely ignore "rows" in the settings). But if I use rows = database$ppos <3 ; then i got the message:
Error in matrix(0, nrow = length(alternatives), ncol = ncol(explanators) * :
invalid 'ncol' value (too large or NA)

So the problem only occurs if some rows should be excluded. If I do the same with the offered dataset and code of example_1.r , all functions and there is also no problem, although some rows would be excluded. But since my code is almost the same, I cannot understand what I do wrong.

Code: Select all

### Clear memory
rm(list = ls())

### Load Apollo library
library(apollo)

### Initialise code
apollo_initialise()

### Set core controls
apollo_control = list(
  modelName  ="Apollo_testpen_1",
  modelDescr ="Simple MNL model",
  indivID    ="ID"
)

# ################################################################# #
#### LOAD DATA AND APPLY ANY TRANSFORMATIONS                     ####
# ################################################################# #

database = read.csv2("DataSetModelwoX.csv",header=TRUE)
colnames(database)[1] = "ID"


# ################################################################# #
#### ANALYSIS OF CHOICES                                         ####
# ################################################################# #

choiceAnalysis_settings <- list(
  alternatives = c(TL=1, TC=2, TR=3,  ML=4, MC=5, MR=6, DL=7, DC=8, DR=9),
  avail = 1,
  choiceVar    = database$Choice,
  explanators  = database[,c("ppos")],
  rows = database$ppos < 3
)

apollo_choiceAnalysis(choiceAnalysis_settings, apollo_control, database)

output=apollo_choiceAnalysis(choiceAnalysis_settings,apollo_control,database)
PS: When I use a second variable in the explanators like: explanators = database[,c("ppos", "Age")], then I got this error message:
Error in apollo_choiceAnalysis(choiceAnalysis_settings, apollo_control, :
'list' object cannot be coerced to type 'double'

Thanks for any help.

stephanehess
Site Admin
Posts: 440
Joined: 24 Apr 2020, 16:29

Re: Error in apollo_choiceAnalysis_settings

Post by stephanehess » 07 Sep 2021, 09:21

Hi

apologies for the slow reply, the post got lost in the system. Did you manage to resolve this or do you still need help?

Stephane
--------------------------------
Stephane Hess
www.stephanehess.me.uk

Post Reply