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
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Search found 35 matches
- 31 May 2023, 09:41
- Forum: Model specification
- Topic: MNL model in WTP space and the ASC
- Replies: 5
- Views: 30737
Re: MNL model in WTP space and the ASC
Thanks a lot for these insights. It is very useful to have your comments. The reason why we were considering the scale was that the dataset included a split sample, where half of the respondents got one version of the choice cards whereas the other half got another version. Thus we reasoned that the...
- 23 May 2023, 16:33
- Forum: Model specification
- Topic: MNL model in WTP space and the ASC
- Replies: 5
- Views: 30737
Re: MNL model in WTP space and the ASC
Thank you for the very clarifying response. I see the point in keeping to a simpler model compared to more complex when estimating parameters, and the reason I prefer the model in WTP-space is the direct interpretation of the parameters, and not having to think of potential differences in the scale ...
- 11 May 2023, 14:43
- Forum: Model specification
- Topic: MNL model in WTP space and the ASC
- Replies: 5
- Views: 30737
MNL model in WTP space and the ASC
Hello I am running a simple MNL model in WTP space. The model is as follows: V = list() V[["alternative1"]] = b_COST *( asc_SQ + b_SB * SB1 + b_JOB * JOB1 + b_SAL * SAL1 + COST1) V[["alternative2"]] = b_COST *( b_SB * SB2 + b_JOB * JOB2 + b_SAL * SAL2 + COST2) V[["alternativ...
- 13 Mar 2023, 09:42
- Forum: Models and estimation
- Topic: interpretation of class allocation in LC models
- Replies: 2
- Views: 17276
Re: interpretation of class allocation in LC models
Yes, very helpful indeed!
Thank you.
will try to keep posts to the Forum strictly apollo-related!!
I am very happy that this forum exists.
BR,
Margrethe
Thank you.
will try to keep posts to the Forum strictly apollo-related!!
I am very happy that this forum exists.
BR,
Margrethe
- 02 Mar 2023, 12:37
- Forum: Models and estimation
- Topic: interpretation of class allocation in LC models
- Replies: 2
- Views: 17276
interpretation of class allocation in LC models
Dear prof Hess & Dr Palma We have estimated a LC model including interactions for sex and age in the class-allocation part of the model. The model runs well, but having the results we are somewhat uncertain about how to interpret the estimated parameters (gamma_sex, gamma_age)? Are these paramet...
- 15 Jul 2022, 15:28
- Forum: Post-estimation analysis/use of results
- Topic: confidence intervals
- Replies: 4
- Views: 26173
Re: confidence intervals
Hi again David I have a question related to that of the CIs. I am running a Poe test to find out whether two coefficients are equal or not. I use the mded package, and this code: coef_land_T <- rnorm(1000, coef(model)[12], sqrt(vcov(model)[12,12])) coef_land_B <- rnorm(1000, coef(model)[7], sqrt(vco...
- 15 Jul 2022, 09:01
- Forum: Post-estimation analysis/use of results
- Topic: confidence intervals
- Replies: 4
- Views: 26173
Re: confidence intervals
Thanks a lot.
Very useful to have this CI code!!
best regards,
Margrethe
Very useful to have this CI code!!
best regards,
Margrethe
- 30 Jun 2022, 14:06
- Forum: Post-estimation analysis/use of results
- Topic: confidence intervals
- Replies: 4
- Views: 26173
confidence intervals
Hi I am using the following code to calculate confidence intervals for estimated coefficients: s.e. = sqrt(vcov(model)[11,11]) ci95 = function(coef_bunn_T) { t.value = 1.96 standard.error = s.e. ci = t.value*standard.error cat("95% Confidence Interval =", mean(coef_bunn_T) - ci, "to &...
- 30 Jun 2022, 13:03
- Forum: Estimation results
- Topic: high ASC-coefficients in model in wtp-space
- Replies: 1
- Views: 12059
high ASC-coefficients in model in wtp-space
Hi I estimated this model in wtp-space: V = list() V[['alt1']] = Certain *(cost_B*(asc_B + torsk_B * KT1 + Cost1 + laks_B * VL1 + bunn_B * HB1 + land_B * KL1))+ (1-Certain)*(cost_T*(asc_T + torsk_T * KT1 + Cost1 + laks_T * VL1 + bunn_T * HB1 + land_T * KL1)) V[['alt2']] = Certain * (cost_B*(torsk_B ...
- 03 Jan 2022, 14:10
- Forum: Model specification
- Topic: model in WTP-space and ASCs
- Replies: 1
- Views: 10249
model in WTP-space and ASCs
Hi I have specified the following model; V = list() V[['alt1']] = Certain *(cost_B*(asc_B + torsk_B * KT1 + Cost1 + laks_B * VL1 + bunn_B * HB1 + land_B * KL1))+(1-Certain)*(cost_T*(asc_T + torsk_T * KT1 + Cost1 + laks_T * VL1 + bunn_T * HB1 + land_T * KL1)) V[['alt2']] = Certain * (cost_B*(torsk_B ...