Hi
how about your MNL results? Were they also unexpectedly high?
Stephane
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Search found 1348 matches
- 22 Feb 2026, 09:14
- Forum: Models and estimation
- Topic: WTP estimates
- Replies: 1
- Views: 1906
- 13 Feb 2026, 10:37
- Forum: Estimation results
- Topic: Unexpected sign for remuneration coefficient
- Replies: 5
- Views: 4298
Re: Unexpected sign for remuneration coefficient
Hi
this seems more of an issue of how people reacted to the attribute, rather than a modelling issue per se. Did you run a focus group or pilot at all?
Stephane
this seems more of an issue of how people reacted to the attribute, rather than a modelling issue per se. Did you run a focus group or pilot at all?
Stephane
- 04 Feb 2026, 11:37
- Forum: Model specification
- Topic: Combining experiments and feasibility of using nested logit structure
- Replies: 1
- Views: 2626
Re: Combining experiments and feasibility of using nested logit structure
Hi
not sure what your aim is re the alpha parameter, but otherwise, combining the models would be fine, of course with a scale parameter. There's an example on the Apollo website
Regarding NL, this won't really work. As you'll only ever have two alternatives available at a time, the probs would be ...
not sure what your aim is re the alpha parameter, but otherwise, combining the models would be fine, of course with a scale parameter. There's an example on the Apollo website
Regarding NL, this won't really work. As you'll only ever have two alternatives available at a time, the probs would be ...
- 03 Feb 2026, 07:42
- Forum: Estimation results
- Topic: Unexpected sign for remuneration coefficient
- Replies: 5
- Views: 4298
Re: Unexpected sign for remuneration coefficient
To diagnose it further, can you try a model with a categorical treatment of price, just to see the non-linearity
you might also want to think about a nested logit model
you might also want to think about a nested logit model
- 23 Jan 2026, 12:27
- Forum: Estimation results
- Topic: Mixed Logit Model for BWS: differences between Apollo and Stata estimations + baseline option issue in Apollo
- Replies: 3
- Views: 4217
Re: Mixed Logit Model for BWS: differences between Apollo and Stata estimations + baseline option issue in Apollo
Hi
they are clearly not the same model. You need to get exactly the same results for MNL. Can you show us the specification for both packages? I note the Stata one has a constant for example
Regarding item_4, this will work, but you need to include it in the utility functions of course
Stephane
they are clearly not the same model. You need to get exactly the same results for MNL. Can you show us the specification for both packages? I note the Stata one has a constant for example
Regarding item_4, this will work, but you need to include it in the utility functions of course
Stephane
- 22 Jan 2026, 07:46
- Forum: Estimation results
- Topic: Mixed Logit Model for BWS: differences between Apollo and Stata estimations + baseline option issue in Apollo
- Replies: 3
- Views: 4217
Re: Mixed Logit Model for BWS: differences between Apollo and Stata estimations + baseline option issue in Apollo
Hi
as a first step, can you confirm that you get exactly the same results with MNL in both packages?
Stephane
as a first step, can you confirm that you get exactly the same results with MNL in both packages?
Stephane
- 22 Jan 2026, 07:45
- Forum: Estimation results
- Topic: Unexpected sign for remuneration coefficient
- Replies: 5
- Views: 4298
Re: Unexpected sign for remuneration coefficient
Hi
this could well have to do with your first alternative, which I assume is an opt-out? What were the levels for that?
Stephane
this could well have to do with your first alternative, which I assume is an opt-out? What were the levels for that?
Stephane
- 28 Dec 2025, 14:51
- Forum: Bug reports
- Topic: Element gradientObs not in model object
- Replies: 3
- Views: 8029
Re: Element gradientObs not in model object
sorry, not at present. It should be possible in a month or so
- 17 Dec 2025, 13:36
- Forum: Bug reports
- Topic: Element gradientObs not in model object
- Replies: 3
- Views: 8029
Re: Element gradientObs not in model object
hi
this was in an earlier version of Apollo, and is not currently implemented. It will be added again in the near future, but requires a change to the bgw optimiser first
Stephane
this was in an earlier version of Apollo, and is not currently implemented. It will be added again in the near future, but requires a change to the bgw optimiser first
Stephane
- 15 Dec 2025, 10:46
- Forum: Estimation results
- Topic: Difference between standard vs robust t-ratios
- Replies: 1
- Views: 4190
Re: Difference between standard vs robust t-ratios
Hi
yes, these differences are very large, and also go in the opposite direction of what we typically see. Did you try a basic version of the model, without all the attributes?
Stephane
yes, these differences are very large, and also go in the opposite direction of what we typically see. Did you try a basic version of the model, without all the attributes?
Stephane