Hi
it looks like you are not including those socio-demographics in the random coefficients, so they would not affect the MRS
Regarding your code, you will want to use subset instead of multiplication by a 0/1 indicator
Stephane
Important: Read this before posting to this forum
- 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.
- 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
- Before asking a question on the forum, users are kindly requested to follow these steps:
- Check that the same issue has not already been addressed in the forum - there is a search tool.
- 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
- Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
- Make sure that R is using the latest official release of Apollo.
- Users can check which version they are running by entering packageVersion("apollo").
- Then check what is the latest full release (not development version) at http://www.ApolloChoiceModelling.com/code.html.
- To update to the latest official version, just enter install.packages("apollo"). To update to a development version, download the appropriate binary file from http://www.ApolloChoiceModelling.com/code.html, and install the package from file
- If the above steps do not resolve the issue, then users should follow these steps when posting a question:
- provide full details on the issue, including the entire code and output, including any error messages
- 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 977 matches
- 02 Apr 2024, 15:15
- Forum: Post-estimation analysis/use of results
- Topic: Marginal rate of substitution for different sociodemographic groups
- Replies: 1
- Views: 147
- 02 Apr 2024, 15:11
- Forum: Estimation results
- Topic: Missing model-fit parameters
- Replies: 1
- Views: 132
Re: Missing model-fit parameters
Hi
please update to the newest version of Apollo and see if that fixes it
Thanks
please update to the newest version of Apollo and see if that fixes it
Thanks
- 02 Apr 2024, 14:14
- Forum: Errors during model validation and/or estimation.
- Topic: No covariance matrix
- Replies: 1
- Views: 163
Re: No covariance matrix
Hi
can you tell us more about your data, i.e. how many levels there are for each of the attributes
can you tell us more about your data, i.e. how many levels there are for each of the attributes
- 23 Feb 2024, 11:32
- Forum: Estimation results
- Topic: Unreasonable estimate for price and other attributes
- Replies: 5
- Views: 765
Re: Unreasonable estimate for price and other attributes
Hi Cuong You have 3 alternatives, but you are only estimating one constant. You can estimate J-1 constants, i.e. 2 My question was whether your third alternative in the survey is different from the other two, i.e. does it use different levels, etc? Regarding categorical, what I mean is that you dumm...
- 23 Feb 2024, 11:26
- Forum: Model specification
- Topic: Start values for wta parameter
- Replies: 1
- Views: 243
Re: Start values for wta parameter
Anat
Can you provide us with a bit more detail, please, e.g. a screenshot of a SC task?
Thanks
Stephane
Can you provide us with a bit more detail, please, e.g. a screenshot of a SC task?
Thanks
Stephane
- 23 Feb 2024, 11:22
- Forum: Estimation results
- Topic: MNL Model Estimation with covariate in WTP Space - Difficulty including covariate and to check correctness
- Replies: 1
- Views: 215
Re: MNL Model Estimation with covariate in WTP Space - Difficulty including covariate and to check correctness
Nico if you look at your partial derivatives of the utility functions, you will see that they are now different for the non price attributes given that you have placed the age interaction with cost on the parameter b_price_value so now you are introducing scale heterogeneity as a function of age. On...
- 23 Feb 2024, 11:12
- Forum: Post-estimation analysis/use of results
- Topic: WTP distribution in preference space
- Replies: 1
- Views: 261
Re: WTP distribution in preference space
Hi
Yes, a ratio of two lognormals is a lognormals, and if one (and only one) of the two is a negative lognormal, then the ratio is negative lognormal too
Re your plots, are you using a low number of draws? Maybe also try without imposing the limits
Stephane
Yes, a ratio of two lognormals is a lognormals, and if one (and only one) of the two is a negative lognormal, then the ratio is negative lognormal too
Re your plots, are you using a low number of draws? Maybe also try without imposing the limits
Stephane
- 23 Feb 2024, 11:08
- Forum: Model specification
- Topic: ICLV model specification in unlabelled form
- Replies: 6
- Views: 6161
Re: ICLV model specification in unlabelled form
Hi
In order for us to help you, you need to show us the output, i.e. the parameter estimates.
Can you please also confirm that a MNL and mixed logit model worked on the data before moving to hybrid choice?
Thanks
In order for us to help you, you need to show us the output, i.e. the parameter estimates.
Can you please also confirm that a MNL and mixed logit model worked on the data before moving to hybrid choice?
Thanks
- 06 Feb 2024, 19:56
- Forum: Estimation results
- Topic: Unreasonable estimate for price and other attributes
- Replies: 5
- Views: 765
Re: Unreasonable estimate for price and other attributes
Hi
first, you should always use a full set (i.e. J-1) alternative specific constants.
But is your third alternative systematically different from the other two which could lead to the issues you're seeing
Stephane
first, you should always use a full set (i.e. J-1) alternative specific constants.
But is your third alternative systematically different from the other two which could lead to the issues you're seeing
Stephane
- 03 Feb 2024, 14:05
- Forum: Model estimation
- Topic: Estimation of MNL and MMNL in WTP space issues
- Replies: 5
- Views: 966
Re: Estimation of MNL and MMNL in WTP space issues
Hi
I also need to know the LL you get with MNL and in WTP space, please, i.e. where it runs out of iterations
Stephane
I also need to know the LL you get with MNL and in WTP space, please, i.e. where it runs out of iterations
Stephane