Dear Stephane and David,
I have been working with the eMDC model since May 2025, and I have been able to specify and estimate a model. I read the published paper on eMDC and followed all the recommendations, including those available in this forum. For example, I reduced the number of parameters ...
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Search found 13 matches
- 04 Sep 2025, 09:41
- Forum: Model estimation
- Topic: eMDC model with 28 alternatives (Burger ingredients)
- Replies: 1
- Views: 1361
- 02 Mar 2025, 22:00
- Forum: Model estimation
- Topic: Latent class model with covariates in class allocation model
- Replies: 2
- Views: 12788
Re: Latent class model with covariates in class allocation model
Hi Stephane,
Many thanks for your time and response.
The model fit didn’t change much—only around a 1% difference in AIC, BIC, and CAIC—so I decided to keep the model with four classes (see below - D is difference).
Classes #parametrs LL Adjusted R squared BIC AIC CAIC
2 43 -10296.43 0.1924 ...
Many thanks for your time and response.
The model fit didn’t change much—only around a 1% difference in AIC, BIC, and CAIC—so I decided to keep the model with four classes (see below - D is difference).
Classes #parametrs LL Adjusted R squared BIC AIC CAIC
2 43 -10296.43 0.1924 ...
- 10 Feb 2025, 12:58
- Forum: Model estimation
- Topic: Latent class model with covariates in class allocation model
- Replies: 2
- Views: 12788
Latent class model with covariates in class allocation model
Dear Stephane,
Thanks for your support in this forum.
I am running a model with many parameters and using Apollo’s search functions for starting values. Models with up to four classes run fine, but with five classes, one parameter (ercr2) has an extreme estimate (-250.99 vs. others mostly below ...
Thanks for your support in this forum.
I am running a model with many parameters and using Apollo’s search functions for starting values. Models with up to four classes run fine, but with five classes, one parameter (ercr2) has an extreme estimate (-250.99 vs. others mostly below ...
- 19 Oct 2023, 13:54
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 223389
Re: Unconditionals
Hi Stephane,
Thanks for your time and support in this forum. I see the version I am using is 0.3.0, so not quite sure when you say the error is related to an old version of Apollo. Of course, I will try to update to the newest version (if available) and see if the error can be eliminated ...
Thanks for your time and support in this forum. I see the version I am using is 0.3.0, so not quite sure when you say the error is related to an old version of Apollo. Of course, I will try to update to the newest version (if available) and see if the error can be eliminated ...
- 13 Oct 2023, 15:47
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 223389
Re: Unconditionals
Yes, I am glad to share the code.
### Clear memory
rm(list = ls())
### Load Apollo library
library(apollo)
### Initialise code
apollo_initialise()
### Set core controls
apollo_control = list(
modelName = "LC-MXL",
modelDescr = "LC-MXL-classes",
indivID = "ID",
mixing = TRUE,
panelData ...
### Clear memory
rm(list = ls())
### Load Apollo library
library(apollo)
### Initialise code
apollo_initialise()
### Set core controls
apollo_control = list(
modelName = "LC-MXL",
modelDescr = "LC-MXL-classes",
indivID = "ID",
mixing = TRUE,
panelData ...
- 13 Oct 2023, 10:53
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 223389
Re: Unconditionals
Thanks for your reply Stephane, I am using version 0.3.0.
/Mohammed
/Mohammed
- 11 Oct 2023, 21:12
- Forum: Errors during model validation and/or estimation.
- Topic: Unconditionals
- Replies: 13
- Views: 223389
Unconditionals
Dear Stephane,
I am encountering some problems when I am trying to derive the unconditional for some parameters after successfully estimating my model (a latent class mixed logit model).
apollo_unconditionals(model, apollo_probabilities, apollo_inputs)
Error in length(apollo_draws) && is.na ...
I am encountering some problems when I am trying to derive the unconditional for some parameters after successfully estimating my model (a latent class mixed logit model).
apollo_unconditionals(model, apollo_probabilities, apollo_inputs)
Error in length(apollo_draws) && is.na ...
- 09 Mar 2022, 15:02
- Forum: Post-estimation analysis/use of results
- Topic: delta method to calculate WTP (normal and log-normal parameters)
- Replies: 12
- Views: 155644
Re: delta method to calculate WTP (normal and log-normal parameters)
Stephane, thanks really for your help. I appreciate it very much, it helps a lot.
Best,
Mohammed
Best,
Mohammed
- 09 Mar 2022, 14:45
- Forum: Post-estimation analysis/use of results
- Topic: delta method to calculate WTP (normal and log-normal parameters)
- Replies: 12
- Views: 155644
Re: delta method to calculate WTP (normal and log-normal parameters)
Thank you Stephane.
Yes, that is true, there is a SD as WTP is normal. But my question was really how to estimate the WTP in Apollo when you have random parameters in your model. Sorry if I misunderstood something here. As you said, I need to specify a closed form for the mean and sd to use the ...
Yes, that is true, there is a SD as WTP is normal. But my question was really how to estimate the WTP in Apollo when you have random parameters in your model. Sorry if I misunderstood something here. As you said, I need to specify a closed form for the mean and sd to use the ...
- 09 Mar 2022, 14:10
- Forum: Post-estimation analysis/use of results
- Topic: delta method to calculate WTP (normal and log-normal parameters)
- Replies: 12
- Views: 155644
Re: delta method to calculate WTP (normal and log-normal parameters)
Hi Stephane,
Thanks indeed for your response.
Okay good to know this. Given that my model is specified in preference space where utility is linear in parameters, can't I just take the ratio of the non-price attribute and the price attribute although the non-price parameters are random? In the ...
Thanks indeed for your response.
Okay good to know this. Given that my model is specified in preference space where utility is linear in parameters, can't I just take the ratio of the non-price attribute and the price attribute although the non-price parameters are random? In the ...