# Log

• 2026-10-30 P0 passed: contract written.
• 2026-10-30 Decision (made before computing any test-period errors): model = AR(2) on first differences of UNRATE with intercept, OLS, estimation sample all available data from 1948-01 up to origin; iterated multi-step forecasts, cumulated to levels. No model selection on the test window. Rationale: standard simple benchmark; pre-specified to avoid test-set snooping.
• 2026-10-30 Session resumed after interruption; P1 audit done (one missing month 2025-10, COVID spike kept). Missing-value handling decided (see data_audit.md).
• 2026-10-30 P1-P3 passed; results computed (AR2_diff slightly worse than naive). P4 checks all PASS; running gate.
• 2026-10-30 P4 passed (gate 20261030T060321.751925Z.json), P5 passed; final gate 20261030T060328.958349Z.json. Task complete.