{
  "as_of": "2026-07-23",
  "measurement": {
    "identity": "Out-of-sample in-game win-probability calibration, split into static, score-only, and combined arms."
  },
  "arms": [
    {
      "sport": "NBA",
      "n": null,
      "observed_on": "2026-07-23",
      "static_brier": 0.209,
      "score_only_brier": 0.172,
      "combined_brier": 0.159,
      "mechanical_share": "~73%",
      "model_prior_share": "-0.014 (~27%)"
    },
    {
      "sport": "MLB",
      "n": null,
      "observed_on": "2026-07-23",
      "static_brier": 0.241,
      "score_only_brier": 0.128,
      "combined_brier": 0.126,
      "mechanical_share": "~99%",
      "model_prior_share": "-0.001 (~1%)"
    }
  ],
  "sources": [
    {
      "path": "docs/INGAME_PROOF.md",
      "role": "Recorded measurement table and interpretation."
    },
    {
      "path": "scripts/platformkit/proof_nba/ingame_accuracy.py",
      "role": "Original NBA analysis path."
    },
    {
      "path": "scripts/platformkit/proof_mlb/ingame_accuracy.py",
      "role": "Original MLB analysis path."
    }
  ]
}