{
  "paper": "PLUM",
  "arxiv_id": "2510.07784",
  "dataset": "MovieLens 1M",
  "seed": 42,
  "configuration": {
    "base_model": "HuggingFaceTB/SmolLM2-135M",
    "sid_cardinalities": [
      512,
      256,
      128
    ],
    "cpt_steps": 240,
    "sft_steps": 240,
    "batch_size": 16,
    "learning_rate": 0.0001,
    "beam_size": 10,
    "evaluated_users": 200
  },
  "sid": {
    "uniqueness": 0.9832703723691312,
    "valid_generation_rate": 1.0
  },
  "variants": {
    "R1": {
      "pretrained_llm": false,
      "cpt": false,
      "cpt_final_loss": null,
      "sft_final_loss": 3.502263271808624,
      "recall_at_10": 0.005,
      "ndcg_at_10": 0.001934264036172708
    },
    "R2": {
      "pretrained_llm": true,
      "cpt": false,
      "cpt_final_loss": null,
      "sft_final_loss": 3.72085839509964,
      "recall_at_10": 0.0,
      "ndcg_at_10": 0.0
    },
    "CR1": {
      "pretrained_llm": false,
      "cpt": true,
      "cpt_final_loss": 2.636583960056305,
      "sft_final_loss": 2.593324339389801,
      "recall_at_10": 0.005,
      "ndcg_at_10": 0.005
    },
    "CR2": {
      "pretrained_llm": true,
      "cpt": true,
      "cpt_final_loss": 2.7960814356803896,
      "sft_final_loss": 3.168586015701294,
      "recall_at_10": 0.0,
      "ndcg_at_10": 0.0
    }
  },
  "conclusion": "CPT improved SFT optimization for random initialization but did not improve Recall@10; pretrained initialization did not improve local ranking metrics at this scale.",
  "excluded_runs": [
    {
      "target_sft_steps": 1000,
      "reason": "Legacy continuation rebuilt semantic IDs instead of restoring them, so token semantics were not guaranteed to remain identical. The run is excluded from reported metrics."
    }
  ],
  "schema_version": 2,
  "manifest_ref": "reproduction:plum",
  "evaluation_protocol": {
    "tier": "l3_paper_pipeline",
    "seeds": [
      42
    ],
    "formal_comparison": false,
    "claim_policy": "single/few-seed smoke result; do not claim a stable improvement"
  },
  "provenance": {
    "artifact_path": "docs/reproductions/2510.07784-plum/metrics/movielens-1m-seed42.json",
    "historical_migration": "historical-metrics-v2-2026-08-09",
    "original_code_commit": "not recorded",
    "dataset_fingerprint": "not recorded in historical artifact"
  }
}