Log
- 2026-10-30 P0: read TASK.md/codebook; contract written.
- 2026-10-30 P1: audit done; decisions: drop rating_2025 (look-ahead), drop 40 exact duplicates, drop 300 rows with missing outcome (2022).
- 2026-10-30 P2: baseline default_rate = 0.1211 on estimation sample.
- 2026-10-30 P3: analysis.py implemented (no randomness; random_seed null).
- 2026-10-30 P4 passed (gate receipt 20261030T044918.902713Z); P5 report+claims written, final gate run.
- 2026-10-30 Final gate PASSED (20261030T044939.244747Z). Task complete.