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  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
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    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
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Search found 11 matches

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by sethyash52
22 Jun 2023, 18:47
Forum: Other
Topic: negative sign in the range of log-uniform distribution
Replies: 1
Views: 2663

negative sign in the range of log-uniform distribution

Hello Prof. Stephane, I have considered that the coefficients of alternative attributes follows log-uniform distribution by taking the exponential of uniform distribution. But standard deviation, which represents the range of log-uniform distribution is coming out negative in the purchase price vari...
by sethyash52
16 Apr 2023, 22:28
Forum: Examples (existing and requests for new ones)
Topic: Examples given not clear
Replies: 1
Views: 3216

Examples given not clear

Hi Stephane,

Can you please make me clear about the difference between the Hybrid_with_OL and Hybrid_LC_with_OL

Thanks,
Yash
by sethyash52
16 Apr 2023, 01:22
Forum: Model specification
Topic: ICLV model using ordered measurement model for indicators
Replies: 1
Views: 718

ICLV model using ordered measurement model for indicators

Hi Stephane, I am replicating the "ICLV ordered logit attitudinal model" used in your paper "Using ordered attitudinal indicators in a latent variable choice model: a study of the impact of security on rail travel behaviour" for my data which has binary choice. Can you please che...
by sethyash52
29 Mar 2023, 11:58
Forum: Models and estimation
Topic: interpretation of ICLV model estimates
Replies: 4
Views: 6587

Re: interpretation of ICLV model estimates

Hi Stephane,

The link provided by you for interpreting an ICLV model needs to be fixed. Can you please resend the link?
by sethyash52
20 Mar 2023, 16:15
Forum: Model estimation
Topic: ICLV model using ordered measurement model for indicators
Replies: 2
Views: 3769

ICLV model using ordered measurement model for indicators

Hi Stephane, I am working on an ICLV model with two latent variables using an ordered measurement model for indicators. Please check if my code is correct. I am getting NaN values; I have tried changing the initial values, but the problem still needs to be solved. Thanks ### Clear memory rm(list = l...
by sethyash52
14 Mar 2023, 13:29
Forum: Model estimation
Topic: Result change drastically when increase halton draws from 1500 to 2000 draws
Replies: 1
Views: 3309

Result change drastically when increase halton draws from 1500 to 2000 draws

Hi Stehane, I am considering log-normal distribution in all these results. Why am I getting NaN when I increase the Halton draws to 2000? Also, the parameter estimates change drastically when I change the number of Halton draws from 1500 to 2000. Thanks Estimates: Estimate s.e. t.rat.(0) Rob.s.e. Ro...
by sethyash52
07 Mar 2023, 10:34
Forum: Errors during model validation and/or estimation.
Topic: NaN values in hybrid choice model
Replies: 3
Views: 1171

Re: NaN values in hybrid choice model

The reason for fixing tau as zero is that the model could be overspecified. Also, in one of your papers published in 2012 ("Using ordered attitudinal indicators in a latent variable choice model: a study of the impact of security on rail travel behavior"), one tau of each indicator is fixe...
by sethyash52
05 Mar 2023, 12:29
Forum: Errors during model validation and/or estimation.
Topic: NaN values in hybrid choice model
Replies: 3
Views: 1171

NaN values in hybrid choice model

Hi Stephane, I have attached my code and result below; this is a hybrid choice model with two choices. I do not know why I am getting NaN values. Can you please look into it? # ################################################################# # #### LOAD LIBRARY AND DEFINE CORE SETTINGS #### # #####...
by sethyash52
10 Jan 2023, 12:17
Forum: Estimation results
Topic: MMNL model with panel data
Replies: 1
Views: 2911

MMNL model with panel data

Why I am getting mean and standard deviation of some parameters as statistically insignificant? I have included code and results below please take a look on it. I am working on panel data where there are 4 observations per individual. *****************************************************************...
by sethyash52
10 Sep 2022, 10:38
Forum: Errors during model validation and/or estimation.
Topic: Getting error in Binary logit model
Replies: 3
Views: 2162

Re: Getting error in Binary logit model

I forgot to attach the output so I am attaching my console window here -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------...

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