{
  "model": "SimpleMF (binary preference, BCE + L2, early stop on val AUC)",
  "hyperparams": {
    "k": 8,
    "lr": 0.05,
    "reg": 0.05,
    "epochs": 30,
    "batch": 512
  },
  "train": {
    "rows": 9600,
    "users": 400,
    "prompts": 600
  },
  "test_metrics": {
    "accuracy": 0.6767,
    "auc": 0.734,
    "baseline_accuracy": 0.4833
  },
  "decision_rule": "p_cloud >= 0.5 -> 'cloud', else 'local'",
  "note": "Trained on synthetic demo data; retrain with load_preference_data() on the real file."
}