Explain the behavior of `var_names` in `sample_posterior_predictive`

[ricardoV94]

This is still a draft. I want to add two more examples first about the default ppc and predictions use-cases

TODO

• [ ] Add example about common use for in-sample posterior_predictive
• [ ] Add example about common use for predictions
• [ ] Change conclusion about non-dependence on deterministics or fix behavior
• [ ] Explain volatility when MutableData changes

Link to function docs preview: https://pymcio--7014.org.readthedocs.build/projects/docs/en/7014/api/generated/pymc.sample_posterior_predictive.html

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:books: Documentation preview :books:: https://pymc--7014.org.readthedocs.build/en/7014/

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 92.24%. Comparing base (6c6fd13) to head (08fca4e). Report is 1 commits behind head on main.

Additional details and impacted files

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pymc/sampling/forward.py	95.90% <ø> (ø)

[jessegrabowski]

Last suggestion, getting into the weeds of personal preferences -- I think the API docs would look nicer if you added a title (in bold or italics or w/e) to each of the two examples.

I also think the code in the new section would be easier to follow if you split the model definition plus each function call into a separate code block and wrote your commentary as text instead of code comments.

[ricardoV94]

Last suggestion, getting into the weeds of personal preferences -- I think the API docs would look nicer if you added a title (in bold or italics or w/e) to each of the two examples.

I also think the code in the new section would be easier to follow if you split the model definition plus each function call into a separate code block and wrote your commentary as text instead of code comments.

I agree, even better would be a markdown header, but I don't know if that's supported :D

[jessegrabowski]

I think you can use restructuredtext subsubsection headings, like:

Example 1: Exploring the effect of var_names on outputs ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

See here. It's pretty hideous for viewing in an IDE, though.

[ricardoV94]

That worked @jessegrabowski

[AlexAndorra]

Thanks @ricardoV94 , these clarifications are very much welcome!

I want to add two more examples first about the default ppc and predictions use-cases

Seems like default ppc is done and you only need predictions use-case?

[ricardoV94]

I have addressed several review comments:

• Do not call new draws posterior predictive draws, but add a note for the first case where it is equivalent
• Fix the Deterministics example

I also expanded with two new example sections:

• Posterior predictive checks and predictions: Shows the common use case
• Using new models: Shows how you can use a new model with new variables

It's ready for review again. It is also likely I messed up the myst formatting so any help appreciated.

[ricardoV94]

@AlexAndorra thanks for the review and suggestions. I've addressed them

[ricardoV94]

Things seem to be working. @AlexAndorra wanna do one last pass?