{
  "dataset": "WikiText-2",
  "seed": 42,
  "steps_per_variant": 30,
  "baseline": {
    "architecture": "llama_modern",
    "lm_loss": 5.7470527,
    "perplexity": 313.266,
    "parameters": 139584
  },
  "method": {
    "architecture": "native_sparse_attention",
    "lm_loss": 5.7148753,
    "perplexity": 303.3464,
    "parameters": 141144,
    "attention_edge_fraction": 0.563462,
    "compression_block": 8,
    "selected_blocks": 1,
    "local_window": 8
  },
  "relative": {
    "lm_loss_percent": -0.5599,
    "perplexity_percent": -3.1665
  },
  "schema_version": 2,
  "manifest_ref": "reproduction:native-sparse-attention",
  "evaluation_protocol": {
    "tier": "l2_public_dataset",
    "seeds": [
      42
    ],
    "formal_comparison": false,
    "claim_policy": "single/few-seed smoke result; do not claim a stable improvement"
  },
  "provenance": {
    "artifact_path": "docs/reproductions/2502.11089-native-sparse-attention/metrics/wikitext2-seed42.json",
    "historical_migration": "historical-metrics-v2-2026-08-09",
    "original_code_commit": "not recorded",
    "dataset_fingerprint": "not recorded in historical artifact"
  }
}