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Element gradientObs not in model object

Report bugs or highlight issues with Apollo functions. At a minimum, please include the part of the output where you believe the bug is manifested. Ideally, please share your model file.
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sbuescher
Posts: 2
Joined: 10 Dec 2025, 15:30

Element gradientObs not in model object

Post by sbuescher »

After estimating models using apollo, for example the example model in https://www.apollochoicemodelling.com/f ... variates.r, I cannot extract the element gradientObs from the model object.
According to the manual (https://www.apollochoicemodelling.com/f ... Apollo.pdf, p.210), it should be included in the model object of all models.
For a current project, I require the gradient contributions of individual observations.
Am I missing something, or has this feature been removed?
Thanks in advance for your help.
stephanehess
Site Admin
Posts: 1357
Joined: 24 Apr 2020, 16:29

Re: Element gradientObs not in model object

Post by stephanehess »

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
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Stephane Hess
www.stephanehess.me.uk
sbuescher
Posts: 2
Joined: 10 Dec 2025, 15:30

Re: Element gradientObs not in model object

Post by sbuescher »

Hello Stephane,
Thank you for your response and the clarification!
Is there currently any other way to extract the score contributions on the observational or the individual level?
Kind regards
Sebastian
stephanehess
Site Admin
Posts: 1357
Joined: 24 Apr 2020, 16:29

Re: Element gradientObs not in model object

Post by stephanehess »

sorry, not at present. It should be possible in a month or so
--------------------------------
Stephane Hess
www.stephanehess.me.uk
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