{
  "schema_version": "1.0.0",
  "analysis_date": "2026-08-25",
  "status": "unreviewed internal secondary analysis",
  "analysis_script_sha256": "34469f8a8c03cabaf6ac4eb15ba873154a3eeb59352b255810b5727ad1c08e04",
  "input_sha256": {
    "features_pooled_parquet": "b9bebb3d708140bc5d8cdb217a669e91440dc4071866d13f858485d007b24fc1",
    "frozen_splits_json": "fdeea2ea6b156de472a90230bdc8e1ad1d71b9616d1ab85dd170bedbd15c4e55",
    "training_frozen_standardization_json": "a1037d1658165e48eb8923f4d65a1a42b7a0a35d0f47b0ab281f8fda2f109ce0",
    "feature_extraction_script": "5c48bbd1bd33edb6ee9ee1f46c2f7c211a135ca82b210c677db3c9b3cd0f19cf",
    "feature_definition_script": "c25cd289f828568a83d8a54eaf2ddb3eee9cbabada4e16766ac707c09b971229",
    "peak_correction_script": "2f2a51b6d71431cba1e02e6b3989a043844ebe2c2bc036cc4acff3bcb86b910c"
  },
  "cohort": "autonomic_aging",
  "frozen_held_out_subjects": 211,
  "eligible_subjects": 202,
  "excluded_subjects_with_fewer_than_two_windows": 9,
  "published_subject_identifiers": false,
  "features": {
    "count": 30,
    "names": [
      "MEAN_RR",
      "MEDIAN_RR",
      "SDNN",
      "RMSSD",
      "pNN20",
      "pNN50",
      "HR_mean",
      "HR_std",
      "CVNN",
      "RR_range",
      "VLF_power",
      "LF_power",
      "HF_power",
      "TP_power",
      "LF_norm",
      "HF_norm",
      "LF_HF_ratio",
      "LFn_HFn_ratio",
      "SD1",
      "SD2",
      "SD1_SD2",
      "CSI",
      "CVI",
      "SampEn",
      "ApEn",
      "DFA_alpha1",
      "DFA_alpha2",
      "HFD",
      "KFD",
      "Poincare_SD_ellipse_area"
    ],
    "standardization": "median and robust scale frozen on training data",
    "similarity": "cosine",
    "nonfinite_values_replaced_with_zero_after_standardization": 0
  },
  "upstream_feature_generation": {
    "ecg_channel": "ECG1; this is lead I in two-channel Task Force Monitor records and is a limitation of the existing Paper 3 feature artifact",
    "rr_physiological_gate_ms": [
      300,
      2000
    ],
    "peak_correction": "Lipponen-Tarvainen/Kubios before windowing",
    "windowing": "consecutive non-overlapping 300-beat windows"
  },
  "protocol": {
    "candidate_set": "fixed closed set of 202 held-out subjects",
    "enrollment": "first retained non-overlapping 300-beat window",
    "query": "immediately following retained non-overlapping 300-beat window",
    "windows_per_subject_used": 2,
    "query_in_enrollment_template": false,
    "model_fit_on_held_out_subjects": false,
    "one_query_per_subject": true
  },
  "metrics": {
    "top_1": {
      "hits": 62,
      "queries": 202,
      "accuracy": 0.306931,
      "random_rank_chance": 0.00495,
      "wilson_95": [
        0.247424,
        0.373644
      ],
      "fixed_candidate_bootstrap": {
        "method": "fixed-candidate query-subject bootstrap",
        "replicates": 20000,
        "seed": 20260825,
        "resampling_unit": "one query subject with one query window",
        "candidate_set_recomputed": false,
        "duplicate_draws_do_not_create_new_candidate_ids": true,
        "median": 0.306931,
        "ci_95": [
          0.247525,
          0.371287
        ],
        "interpretation": "Conditional uncertainty across query subjects for this fixed 202-person candidate set; not a population or deployment CI."
      }
    },
    "top_5": {
      "hits": 112,
      "queries": 202,
      "accuracy": 0.554455,
      "random_rank_chance": 0.024752,
      "wilson_95": [
        0.485533,
        0.621345
      ],
      "fixed_candidate_bootstrap": {
        "method": "fixed-candidate query-subject bootstrap",
        "replicates": 20000,
        "seed": 20260825,
        "resampling_unit": "one query subject with one query window",
        "candidate_set_recomputed": false,
        "duplicate_draws_do_not_create_new_candidate_ids": true,
        "median": 0.554455,
        "ci_95": [
          0.485149,
          0.618812
        ],
        "interpretation": "Conditional uncertainty across query subjects for this fixed 202-person candidate set; not a population or deployment CI."
      }
    },
    "top_10": {
      "hits": 133,
      "queries": 202,
      "accuracy": 0.658416,
      "random_rank_chance": 0.049505,
      "wilson_95": [
        0.590606,
        0.720313
      ],
      "fixed_candidate_bootstrap": {
        "method": "fixed-candidate query-subject bootstrap",
        "replicates": 20000,
        "seed": 20260825,
        "resampling_unit": "one query subject with one query window",
        "candidate_set_recomputed": false,
        "duplicate_draws_do_not_create_new_candidate_ids": true,
        "median": 0.658416,
        "ci_95": [
          0.594059,
          0.722772
        ],
        "interpretation": "Conditional uncertainty across query subjects for this fixed 202-person candidate set; not a population or deployment CI."
      }
    }
  },
  "permutation_test": {
    "method": "bijection permutation of query identity labels",
    "replicates": 20000,
    "seed": 20260825,
    "p_one_sided": {
      "1": 5e-05,
      "5": 5e-05,
      "10": 5e-05
    }
  },
  "direction_sensitivity": {
    "protocol": "swap the first and second windows",
    "top_1_accuracy": 0.341584,
    "top_5_accuracy": 0.559406,
    "top_10_accuracy": 0.643564
  },
  "supersedes_for_public_reporting": {
    "value": "top-5 81.10% on 211 subjects",
    "reason": "The earlier number is retained in the private audit trail but its current public-safe artifacts cannot reproduce the full evaluation chain. Code audit also found an incorrect leave-one-out centroid approximation in the point-estimate path and invalid pseudo-identity competition in its uncertainty procedure."
  },
  "limits": [
    "All enrollment and query windows come from the same recording session.",
    "This tests closed-set linkage, not open-set authentication or identity proof.",
    "It does not establish stability across days, devices, sleep/wake state, or Apple Watch.",
    "Shared session, sensor, preprocessing, or signal artifacts may contribute to linkage.",
    "The fixed-candidate bootstrap interval is not a population-performance interval."
  ]
}