{
  "name": "B-Mo iron ore statistical engine",
  "version": 1,
  "created_utc": "2026-11-14T18:32:54+00:00",
  "trained_on_fake_data": false,
  "training": {
    "deposits": 975,
    "background": 1950,
    "exact_only": false,
    "imagery_window": [
      "2024-01-01",
      "2025-12-31"
    ],
    "buffer_m": 500,
    "composite": "median; Sentinel-2 SCL-masked; Landsat QA_PIXEL-masked",
    "background_rule": "25.0-300.0 km from a deposit, on land, 50% on bare/sparse ground"
  },
  "validation": {
    "engine_model": "Statistical engine (likelihood variant)",
    "scheme": "spatial CV, 10-degree blocks",
    "engine_cv_roc_auc": 0.7816005259697567,
    "engine_deposits_found_at_10pct_false_alarms": 0.4164102564102564,
    "best_ml_model": "XGBoost",
    "best_ml_feature_set": "+terrain",
    "best_ml_cv_roc_auc": 0.8577130834976988
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  "feature_set": "+terrain",
  "engine_mode": "likelihood",
  "scoring": {
    "closeness": {
      "per_feature": "s = exp(-0.5*((x-mean)/std)^2)",
      "combine": "weighted average over available features, x100"
    },
    "likelihood": {
      "per_feature": "llr = clip(log N(x|deposit mean,std) - log N(x|background mean,std), -10, 10)",
      "combine": "S = sum(llr * weight/max_weight) over available features; score = 100/(1+exp(-S/llr_scale))",
      "llr_scale": 16.70671964821434
    },
    "mode_used_below": "likelihood",
    "class_names": [
      "Very low",
      "Low",
      "Moderate",
      "High",
      "Very high"
    ],
    "class_edges_score": [
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      56.82105322793868,
      58.531284836870356,
      59.582799025505466
    ],
    "class_edges_note": "background percentiles 50/75/90/97 of out-of-fold engine scores"
  },
  "features": {
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    "B4": {
      "definition": "red",
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      "auc": 0.3086337935568705,
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    "B8": {
      "definition": "NIR",
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      "background_mean": 0.28083064969382937,
      "background_std": 0.08412121715135522
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    "B11": {
      "definition": "SWIR1",
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      "std": 0.05935811691843387,
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    "B12": {
      "definition": "SWIR2",
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      "auc": 0.29981433267587115,
      "background_mean": 0.2625244268812584,
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    "ferric_oxide": {
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      "auc": 0.4651261012491782,
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    "iron_nd": {
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    "ferrous_iron": {
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    "gossan": {
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    "clay": {
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    "ndvi": {
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    "bsi": {
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      "definition": "Landsat 8/9 ST_B10 (K) 10th percentile",
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    "elevation": {
      "definition": "ALOS AW3D30 DSM (m)",
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    "slope": {
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  }
}