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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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- Check that the same issue has not already been addressed in the forum - there is a search tool.
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- Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
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- 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 8 matches
- 07 Feb 2023, 20:11
- Forum: Post-estimation analysis/use of results
- Topic: Delta method in random parameter models
- Replies: 14
- Views: 18053
Re: Delta method in random parameter models
Hi Stephane, I just want to clarify that I understand correctly from your explanation that it is not possible to estimate a mixed logit model in WTP space if one attribute is specified quadratic? I’ve run a mixed logit model in preference space with one attribute specified as quadratic and it worked...
- 14 Mar 2022, 10:16
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane, yes I used the same starting values for the models with 1000, 2000, 2100, and 4000 draws. Since I only got good results without NANs or saddle point convergence for the models in the 2000-2100 draws range, I then used the results of the model with 2100 draws as starting values to run th...
- 09 Mar 2022, 16:00
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane,
I ran the model in preference space with 3000 Sobol draws without any issues; LL: -2733.08
Simone
I ran the model in preference space with 3000 Sobol draws without any issues; LL: -2733.08
Simone
- 07 Mar 2022, 16:37
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane, I have combined the outputs of the model with varying numbers of draws and have attached it. The models are -model with 1000 Sobol draws, Stata results used as starting values, successful convergence but NANs produced -model with 2100 Sobol draws, Stata results used as starting values, ...
- 22 Feb 2022, 16:46
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane, thank you once again for your reply and explanation! I ran the model with varying numbers of Sobol draws, ranging from 1000 to 10000 (always the same starting values). The model always converged but except for when I ran it with 2000 and 2100 Sobol draws, it always produced some NANs an...
- 16 Feb 2022, 11:33
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane, I added a "-" before my cost coefficient in the utility functions to multiply the negative WTP by the negative cost coefficient. ### List of utilities V = list() V[["alt1"]] = -b_payment*(v_biodiv0*(biodiversity1==0) + v_biodiv1*(biodiversity1==1) + v_flood0*(floodOr...
- 15 Feb 2022, 17:42
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
Re: WTP space results - means are negative or NANs produced
Hi Stephane, thank you very much for your quick reply and explanation! The attributes for which I caluclate the WTP are desirable; I have adjusted the definitions of my utility functions. I'm currently re-running the model to check if there are still problems and will get back to you if the identifi...
- 15 Feb 2022, 12:10
- Forum: Estimation results
- Topic: WTP space results - means are negative or NANs produced
- Replies: 13
- Views: 8228
WTP space results - means are negative or NANs produced
Hello, I am running a mixed logit model in WTP space and receive odd results. I am using Sobol draws and starting values that I obtained when I ran the model in Stata with 300 Halton draws (the model wouldn't convergence with a higher number of draws; probably because of the high number of random co...