Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

The benchmark's logistic regression does not converge on German Credit Lending and Healthcare Readmission

Closed
#1,152 0 comments 0 reactions 0 assignees View on GitHub

Maintainers usually reply within 1 day

Nobody has claimed this yet.

Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
57/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
python, scikit-learn

Research direction

Start in faircode/models.py at MODEL_FAMILIES and inspect how build_model constructs logistic regression. Run the reproduction command in the issue, then check the German Credit Lending and Healthcare Readmission audit results under results/ and use diff_results.py to record changed rows. Done when benchmark fits emit no convergence warnings and the pull request lists the changed rows.

Written by the indexing model from the issue text.

Description

bug

Where: faircode/models.py MODEL_FAMILIES, results/.

Current gap: Fitting the benchmark's logistic regression on the S2 features of these two audits raises a scikit-learn ConvergenceWarning: the solver stops at max_iter on unscaled features, so the coefficients, and every number built on them, depend on where it stopped.

Repro:

PYTHONPATH=. python3 -c "import warnings; from faircode.benchmark import load_audit; from faircode.models import build_model; d=load_audit('German Credit Lending'); warnings.simplefilter('error'); build_model('logistic_regression', d.random_state).fit(d.X.iloc[d.idx_train], d.y.iloc[d.idx_train])"

Suggested approach: Scale numeric features inside the estimator (a pipeline) or raise max_iter, rerun the two audits, and record the movement with diff_results.py.

Done when: no benchmark fit warns, and the changed rows are listed in the pull request.

Dominant language
HTML
Stars
47
Forks
45
Avg merge
3h 8m
Merged PRs (30d)
96

Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from yakew7/Fair-Code

All issues in yakew7/Fair-Code

Similar issues

More Machine Learning issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.