Thank you for the advices. We will try the log-uniform;
Damien
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Search found 14 matches
- 05 Jun 2024, 10:41
- Forum: Model specification
- Topic: WTP-space correlation between normals and log-normals
- Replies: 4
- Views: 12040
- 04 Jun 2024, 13:29
- Forum: Model specification
- Topic: WTP-space correlation between normals and log-normals
- Replies: 4
- Views: 12040
Re: WTP-space correlation between normals and log-normals
Thank you for you message and the precisions.
Actually, we wanted the price attribute to be positive (price is a subsidy), so it makes senses to use log-normal.
I ran a model with the previously given code, and I get the following results (see below):
This "looks" satisfactory, but I have two ...
Actually, we wanted the price attribute to be positive (price is a subsidy), so it makes senses to use log-normal.
I ran a model with the previously given code, and I get the following results (see below):
This "looks" satisfactory, but I have two ...
- 03 Jun 2024, 14:03
- Forum: Model specification
- Topic: WTP-space correlation between normals and log-normals
- Replies: 4
- Views: 12040
WTP-space correlation between normals and log-normals
We are trying to estimate a model in the WTA space. (price is a subsidy). To do that, we are making the hypothesis that the price (subsidy) paramater is distributed as a log-normal, and that the other parameters are normally distributed and correlated (including with the price parameter) and can ...
- 17 Jan 2024, 12:10
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 227173
Re: Unconditionals
I am not sure a generic solution was found for this problem?
I have the same kind of message (also for a LC-MXL ANA type of model). I can also share my data and model if needed
I have the same kind of message (also for a LC-MXL ANA type of model). I can also share my data and model if needed
- 15 Dec 2023, 15:18
- Forum: Model specification
- Topic: probabilities of classes vary across choice tasks in a LC-MXL model
- Replies: 1
- Views: 5608
probabilities of classes vary across choice tasks in a LC-MXL model
I am trying to develop a model testing for ANA (using a LC-Mixed Logit model) to avoid inflating the ANA.
Given the high number of possible classes, I am using the methodology proposed by Hole, 2011. This gave me plausible results.
From this model, I wanted to test the idea that attendance might ...
Given the high number of possible classes, I am using the methodology proposed by Hole, 2011. This gave me plausible results.
From this model, I wanted to test the idea that attendance might ...
- 16 Jun 2023, 19:51
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 10946
Re: Log-uniform distribution (always positive)
Indeed, I haven't put enough thought on this, as this will make the distribution start at at 1
Thank you.
Thank you.
- 16 Jun 2023, 06:23
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 10946
Re: Log-uniform distribution (always positive)
Thank you for the clarification about the correlation. For the offset, I assumed that it was equal to zero, but I guess it is better to verify this!
Damien
Damien
- 09 Jun 2023, 13:08
- Forum: Model specification
- Topic: Log-uniform distribution (always positive)
- Replies: 4
- Views: 10946
Log-uniform distribution (always positive)
In a WTP-space mixed logit model, I want to test a log-uniform distribution for the price attribute '(rationale: always positive and avoid long tail of log-normal);
I have two questions (related code below)
1. Is the specification "exp(b_lambda * draws_lambda)" correct if I want a log-uniform ...
I have two questions (related code below)
1. Is the specification "exp(b_lambda * draws_lambda)" correct if I want a log-uniform ...
- 26 Apr 2023, 06:28
- Forum: Model specification
- Topic: Availability of alternatives different for each class in a LC model
- Replies: 4
- Views: 9988
Re: Availability of alternatives different for each class in a LC model
It now runs well including using multithreading. Thank you. Damien
- 25 Apr 2023, 14:28
- Forum: Model specification
- Topic: Availability of alternatives different for each class in a LC model
- Replies: 4
- Views: 9988
Re: Availability of alternatives different for each class in a LC model
Dear Prof Hess,
Just sent a sample data set on your gmail address and contact@apollochoicemodelling.com I hope this will reach you. Thank you.
Damien
Just sent a sample data set on your gmail address and contact@apollochoicemodelling.com I hope this will reach you. Thank you.
Damien