{
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  "record": {
    "schema": "scientific/1",
    "archetype": "scientific",
    "issued_at": "2026-09-16T23:18:20.738013+00:00",
    "subject": {
      "system_under_test": "gradient-boosted trees (XGBoost, 12 lag features) on monthly atmospheric CO2",
      "data": "Mauna Loa monthly atmospheric CO2 (NOAA GML, 1958\u20132026, the Keeling curve)",
      "data_sha256": "c9a91a170d09d16afaaad56c4f383ed4fcb7fa0da967998694842d5c8168bcf3"
    },
    "claim": "the system claims to accurately forecast the scientific series",
    "verdict": "falsified",
    "finding": {
      "gap": "cannot_extrapolate",
      "effect": "the tree-based model's error (7.006 ppm) is 0.2\u00d7 WORSE than the seasonal+drift baseline (1.223 ppm)",
      "detail": "XGBoost cannot extrapolate the monotonic CO2 trend: trees predict within their training range, so on the held-out future (growth accelerated from 0.79 to 2.57 ppm/yr) it under-predicts by up to ~11 ppm. The 'accurate forecast' claim is falsified by a model that structurally cannot forecast a trend"
    },
    "metrics": {
      "rmse_model": 7.006,
      "rmse_seasonal_baseline": 1.223,
      "skill_ratio": 0.175,
      "annual_growth_early": 0.79,
      "annual_growth_late": 2.57,
      "n_months": 822,
      "n_test": 60
    },
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  },
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