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 shengxiao
16 Jun 2021, 14:05
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: parameter does not influence LL

Hi Stephane, Sorry about my late reply. I just want to have more information before reaching out to you. I do not think that I used mixing. The model structure is the same as your publication in Transportation in 2012 (vehicle type and fuel type). My apollo version is apollo_0.2.4. Thanks for the re...
by shengxiao
08 Jun 2021, 13:37
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: parameter does not influence LL

Hi Stephane, It finally works. Thanks so much! But another quick question: I wonder how long does it take to run the model? I have around 80,000 samples, and 12 alternatives. It run for several days already, but did not work out. I wonder whether it is normal. If so, do you have any recommendations ...
by shengxiao
25 May 2021, 16:56
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: parameter does not influence LL

Hi Stephane, I am still confused at how to specify the functions in Apollo. I am testing what factors are related to a combination of residential location and vehicle ownership. This is the reason why I include the same parameters for each alternative. For example, I assume that the age is related t...
by shengxiao
24 May 2021, 21:19
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: parameter does not influence LL

Hi Stephane, That is interesting. I would appreciate it if you can further elaborate. Let me explain further what I am trying to do here. As I can see from the manual, I should change all categorical variables to dummy variables. As you can see in my specifications, this is what I did, and I just dr...
by shengxiao
24 May 2021, 20:37
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: parameter does not influence LL

Hi Stephane, You are correct. I just debugged, and found out that I falsely set my availabilities. I should set full availability. Now, every observation has full flexibility of choices, however, the same error message still shows up. I just paste the result here: Testing likelihood function... Sett...
by shengxiao
19 May 2021, 01:35
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: alternative specific constant (asc) in CNL

Hi Stephan, Here is my output: Testing likelihood function... Overview of choices for CNL model component : Ru_D Ru_N Ru_S SEC_D SEC_N SEC_S SUB_D SUB_N SUB_S URB_D URB_N URB_S Times available 2685.00 819 37156.00 1398.0 893.00 13148.00 1284.00 463.00 15871.00 1015.00 818 6562.00 Times chosen 2685.0...
by shengxiao
17 May 2021, 13:29
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

Re: alternative specific constant (asc) in CNL

Thank you, Stephane. Please see my code for the model specification as follows (This is a cross-nested structure with two nests: residential location denoted by Ru (rural), SEC(secondary city), SUB(suburb), and URB (urban); car ownership denoted by D (car deficit), N (no car), S (car sufficient). Al...
by shengxiao
07 May 2021, 14:30
Forum: Errors during model validation and/or estimation.
Topic: parameter does not influence LL
Replies: 15
Views: 15159

parameter does not influence LL

Dear Apollo team, I am working on a CNL with 12 alternatives. However, I face some challenges in specifying the asc. In your CNL example on the website, you defined acs of different travel modes based on the socioeconomic attributes. In my case, my alternatives are a combination of residential locat...