{
  "metrics": {
    "accuracy": 0.9975,
    "precision": 0.9873417721518988,
    "recall": 0.975,
    "f1": 0.9811320754716981,
    "roc_auc": 0.9999553571428571
  },
  "data_stats": {
    "n_samples": 6000,
    "fraud_rate": 0.06666666666666667,
    "train_size": 4800,
    "test_size": 1200
  },
  "timestamp": "2026-02-04T14:29:29.917435",
  "model_type": "HistGradientBoostingClassifier",
  "features": [
    "amount",
    "hour",
    "day_of_week",
    "distance_from_home",
    "distance_from_last_txn",
    "ratio_to_median",
    "num_txn_last_24h",
    "is_foreign",
    "merchant_risk_score",
    "card_age_months"
  ],
  "retrain_reason": "Drift detected (60% features). Challenger F1 0.9811 meets minimum threshold. Retraining on current distribution is recommended."
}