Dear Prof.,
Thank you very much for your reply. I actually saw how to use the apollo_unconditionals to compute the wtp in one of your replies to a similar question. I will reach out if I have need any other assistance on this.
Best regards,
Gbenga
Important: Read this before posting to this forum
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- 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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Search found 7 matches
- 21 Oct 2024, 07:08
- Forum: Model estimation
- Topic: Computation of WTP for log-uniform Price Specification
- Replies: 2
- Views: 34024
- 03 Oct 2024, 05:54
- Forum: Model estimation
- Topic: Computation of WTP for log-uniform Price Specification
- Replies: 2
- Views: 34024
Computation of WTP for log-uniform Price Specification
Dear Prof.,
Please, I estimated my DCE data in preference space and specify the price coefficient to follow a negative log-uniform distribution. Say B represents my attribute coefficient and p my price coefficient, is it correct to state that WTP for the attribute = B/-exp(p)? Please, I will ...
Please, I estimated my DCE data in preference space and specify the price coefficient to follow a negative log-uniform distribution. Say B represents my attribute coefficient and p my price coefficient, is it correct to state that WTP for the attribute = B/-exp(p)? Please, I will ...
- 30 Sep 2024, 20:53
- Forum: Model estimation
- Topic: Problem with Estimating Scale Parameter
- Replies: 9
- Views: 159156
Re: Problem with Estimating Scale Parameter
Dear Prof.,
Thank you. I think I forgot to mention from the beginning that I did not experience the issue of unexpected (negative) scale values if I specify the price parameter in MMNL to follow normal distribution. I only have the issue when I specify the price parameter to follow log-uniform. And ...
Thank you. I think I forgot to mention from the beginning that I did not experience the issue of unexpected (negative) scale values if I specify the price parameter in MMNL to follow normal distribution. I only have the issue when I specify the price parameter to follow log-uniform. And ...
- 25 Sep 2024, 07:43
- Forum: Model estimation
- Topic: Problem with Estimating Scale Parameter
- Replies: 9
- Views: 159156
Re: Problem with Estimating Scale Parameter
Dear Prof.,
Thank you. In the joint MNL model, scale parameters depend on which scale I fixed to 1.
Here are the results:
First scenario (When Scale for the control group is fixed to 1)
Estimate Std.err.
price -0.001 0.000
afla 2.499 0.236
nafdac 1.990 0.217
untested 1.700 0.202
mu_control 1.000 ...
Thank you. In the joint MNL model, scale parameters depend on which scale I fixed to 1.
Here are the results:
First scenario (When Scale for the control group is fixed to 1)
Estimate Std.err.
price -0.001 0.000
afla 2.499 0.236
nafdac 1.990 0.217
untested 1.700 0.202
mu_control 1.000 ...
- 11 Sep 2024, 16:11
- Forum: Model estimation
- Topic: Problem with Estimating Scale Parameter
- Replies: 9
- Views: 159156
Re: Problem with Estimating Scale Parameter
Prof., thank you. Exactly what I meant too. Please, I attached the results of the group-specific models estimated both in MNL and MMNL.
Thank you for your anticipated response.
Thank you for your anticipated response.
- 10 Sep 2024, 19:25
- Forum: Model estimation
- Topic: Problem with Estimating Scale Parameter
- Replies: 9
- Views: 159156
Re: Problem with Estimating Scale Parameter
Prof., thanks for the prompt response.
1. Yes, I did estimate with MNL and here are the results:
First scenario
Estimate Std.err.
price -0.001 0.000
afla 2.499 0.236
nafdac 1.990 0.217
untested 1.700 0.202
mu_control 1.000 NA
mu_FT 3.354 0.536
mu_ST 2.612 0.383
Second scenario:
Estimate ...
1. Yes, I did estimate with MNL and here are the results:
First scenario
Estimate Std.err.
price -0.001 0.000
afla 2.499 0.236
nafdac 1.990 0.217
untested 1.700 0.202
mu_control 1.000 NA
mu_FT 3.354 0.536
mu_ST 2.612 0.383
Second scenario:
Estimate ...
- 10 Sep 2024, 16:39
- Forum: Model estimation
- Topic: Problem with Estimating Scale Parameter
- Replies: 9
- Views: 159156
Problem with Estimating Scale Parameter
Dear Prof. Hess and Dr. Palma,
Once again, thank you for your efforts in building and supporting the Apollo Software.
I observed an issue while trying to accounting for scale difference in my estimation. My dataset consists of three experimental groups in food choice experiment. Two of the groups ...
Once again, thank you for your efforts in building and supporting the Apollo Software.
I observed an issue while trying to accounting for scale difference in my estimation. My dataset consists of three experimental groups in food choice experiment. Two of the groups ...