{
  "purpose": "synthetic teaching example, not a real-world benchmark",
  "seed": 247022,
  "dataset_sha256": "ee6b7e746c1c11f6df5127cd64115e7c3d58227910cdf8d65451ecd717f14c1a",
  "split": {
    "train": 600,
    "validation": 200,
    "test": 200
  },
  "threshold_grid": [
    0.25,
    0.3,
    0.35,
    0.4,
    0.45,
    0.5,
    0.55,
    0.6,
    0.65,
    0.7,
    0.75
  ],
  "candidates": [
    {
      "name": "a_only",
      "threshold": 0.5,
      "train": {
        "n": 600,
        "accuracy": 0.8183333333333334,
        "tp": 229,
        "tn": 262,
        "fp": 76,
        "fn": 33
      },
      "validation": {
        "n": 200,
        "accuracy": 0.825,
        "tp": 69,
        "tn": 96,
        "fp": 27,
        "fn": 8
      }
    },
    {
      "name": "b_only",
      "threshold": 0.6,
      "train": {
        "n": 600,
        "accuracy": 0.635,
        "tp": 138,
        "tn": 243,
        "fp": 95,
        "fn": 124
      },
      "validation": {
        "n": 200,
        "accuracy": 0.635,
        "tp": 41,
        "tn": 86,
        "fp": 37,
        "fn": 36
      }
    },
    {
      "name": "c_only",
      "threshold": 0.55,
      "train": {
        "n": 600,
        "accuracy": 0.5333333333333333,
        "tp": 139,
        "tn": 181,
        "fp": 157,
        "fn": 123
      },
      "validation": {
        "n": 200,
        "accuracy": 0.545,
        "tp": 39,
        "tn": 70,
        "fp": 53,
        "fn": 38
      }
    },
    {
      "name": "equal_a_b",
      "threshold": 0.55,
      "train": {
        "n": 600,
        "accuracy": 0.7966666666666666,
        "tp": 193,
        "tn": 285,
        "fp": 53,
        "fn": 69
      },
      "validation": {
        "n": 200,
        "accuracy": 0.79,
        "tp": 58,
        "tn": 100,
        "fp": 23,
        "fn": 19
      }
    }
  ],
  "selected": {
    "name": "a_only",
    "threshold": 0.5
  },
  "test": {
    "n": 200,
    "accuracy": 0.81,
    "tp": 64,
    "tn": 98,
    "fp": 27,
    "fn": 11
  },
  "baseline": {
    "constant_class": 0,
    "test": {
      "n": 200,
      "accuracy": 0.625,
      "tp": 0,
      "tn": 125,
      "fp": 0,
      "fn": 75
    }
  },
  "limitations": [
    "IID synthetic rows",
    "single split and seed",
    "accuracy assumes equal error costs",
    "candidate family designed for this exercise",
    "no deployment or historical MASH results"
  ]
}