pymc-devs / pymc-devs/nutpie

pymc: Random Deterministics are currently broken

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Dominant language
Python
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207
Forks
28
Avg merge
7d 21h
Merged PRs (30d)
1

Description

If a deterministic variable uses a RandomVariable, it won't properly update the seed in the expanding_function of the compiled pymc model, as we only use the numba function but do not perform the updates.

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by tracing the compiled PyMC model's expanding_function and the numba function it currently uses, focusing on how RandomVariables and deterministic variables handle seeds. Reproduce the failure with a deterministic variable using a RandomVariable, then verify that the seed is updated correctly during expansion.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
machine-learning
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
45/100

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