{
  "date": "2026-10-13",
  "study": "Classical switched-system Ho-Kalman/ERA baseline on the v2 learned-memory fixture",
  "protocol": "PROTOCOL_ERA.md",
  "protocol_commit": "0e1db34",
  "data": "identical to v2 (learned_memory.build_splits), seeds 41 and 97",
  "metric": "identical to v2: pooled RMSE / RMS true outputs, steps 1-6 open loop",
  "means": {
    "closed": {
      "era4": {
        "current_nrmse": 0.356214,
        "early_nrmse": 0.379002,
        "late_nrmse": 0.449934,
        "future_nrmse": 0.416011,
        "shared_parameters": 286,
        "state_float32_bytes": 16
      },
      "era5": {
        "current_nrmse": 0.276872,
        "early_nrmse": 0.345112,
        "late_nrmse": 0.471303,
        "future_nrmse": 0.413739,
        "shared_parameters": 376,
        "state_float32_bytes": 20
      },
      "era4_pem_posthoc": {
        "current_nrmse": 0.245964,
        "early_nrmse": 0.171495,
        "late_nrmse": 0.130742,
        "future_nrmse": 0.152782,
        "shared_parameters": 290,
        "state_float32_bytes": 16
      },
      "era5_pem_posthoc": {
        "current_nrmse": 0.245711,
        "early_nrmse": 0.174925,
        "late_nrmse": 0.133309,
        "future_nrmse": 0.15581,
        "shared_parameters": 381,
        "state_float32_bytes": 20
      }
    },
    "bridge": {
      "era4": {
        "current_nrmse": 0.327228,
        "early_nrmse": 0.42061,
        "late_nrmse": 0.678057,
        "future_nrmse": 0.564222,
        "shared_parameters": 286,
        "state_float32_bytes": 16
      },
      "era5": {
        "current_nrmse": 0.283706,
        "early_nrmse": 0.318878,
        "late_nrmse": 0.503001,
        "future_nrmse": 0.42134,
        "shared_parameters": 376,
        "state_float32_bytes": 20
      },
      "era4_pem_posthoc": {
        "current_nrmse": 0.261147,
        "early_nrmse": 0.188476,
        "late_nrmse": 0.218206,
        "future_nrmse": 0.204079,
        "shared_parameters": 290,
        "state_float32_bytes": 16
      },
      "era5_pem_posthoc": {
        "current_nrmse": 0.201212,
        "early_nrmse": 0.164336,
        "late_nrmse": 0.194817,
        "future_nrmse": 0.180406,
        "shared_parameters": 381,
        "state_float32_bytes": 20
      }
    }
  },
  "learned_v2_reference": {
    "closed": {
      "predictive4": 0.192687,
      "predictive5": 0.178501,
      "gru5": 0.298002,
      "pca5": 0.787912
    },
    "bridge": {
      "predictive4": 0.200006,
      "predictive5": 0.157058,
      "gru5": 0.24694,
      "pca5": 0.781966
    }
  },
  "primary_verdicts": {
    "closed": {
      "era5_minus_predictive5_future": 0.2352,
      "reading": "learned model adds value beyond the linear Hankel quotient"
    },
    "bridge": {
      "era5_minus_predictive5_future": 0.2643,
      "reading": "learned model adds value beyond the linear Hankel quotient"
    }
  },
  "bridge_question": {
    "closed": {
      "era5_minus_era4_future": -0.0023,
      "predictive5_minus_predictive4_future": -0.0142
    },
    "bridge": {
      "era5_minus_era4_future": -0.1429,
      "predictive5_minus_predictive4_future": -0.0429
    }
  },
  "posthoc_diagnostic": {
    "what": "ERA realization refined by linear prediction-error least squares on the full 6-step training horizon (scipy trf, 40 evaluations, no validation tuning). Same 381 parameters as Predictive5 at n=5. NOT pre-registered; added after the primary result to locate the gap.",
    "pem5_minus_predictive5_future": {
      "closed": -0.0227,
      "bridge": 0.0233
    },
    "pem4_minus_predictive4_future": {
      "closed": -0.0399,
      "bridge": 0.0041
    }
  },
  "limits": [
    "Two apparatus seeds only",
    "The PEM rows are post-hoc diagnostics, not frozen comparisons",
    "Linear models on a nonlinear fixture; no claim about natural images"
  ],
  "paired_vs_regenerated_v2": {
    "source": "CI run 38402521300: v2 learned run regenerated with torch (matched its receipt), ERA regenerated (matched its receipt); 800 test episodes per world (2 seeds x 400); bootstrap 4000; positive = ERA-side worse",
    "closed": {
      "era5_vs_predictive5": {
        "mean": 0.22907,
        "ci95": [
          0.21861,
          0.23943
        ]
      },
      "era4_vs_predictive4": {
        "mean": 0.21784,
        "ci95": [
          0.20758,
          0.22764
        ]
      },
      "era5_pem_posthoc_vs_predictive5": {
        "mean": -0.02098,
        "ci95": [
          -0.02594,
          -0.01561
        ],
        "era_side_wins": 0.625
      },
      "era4_pem_posthoc_vs_predictive4": {
        "mean": -0.03731,
        "ci95": [
          -0.04201,
          -0.03248
        ],
        "era_side_wins": 0.698
      }
    },
    "bridge": {
      "era5_vs_predictive5": {
        "mean": 0.25729,
        "ci95": [
          0.24748,
          0.26693
        ]
      },
      "era4_vs_predictive4": {
        "mean": 0.34497,
        "ci95": [
          0.33201,
          0.35891
        ]
      },
      "era5_pem_posthoc_vs_predictive5": {
        "mean": 0.01347,
        "ci95": [
          0.0078,
          0.01953
        ],
        "era_side_wins": 0.436
      },
      "era4_pem_posthoc_vs_predictive4": {
        "mean": -0.00179,
        "ci95": [
          -0.00717,
          0.00373
        ],
        "era_side_wins": 0.53
      }
    }
  }
}