{
 "status": "ok",
 "generated_at": "2026-07-25T03:52:27.217372+00:00",
 "descriptive_only": true,
 "edge_claimed": false,
 "headline": "Home advantage is real; the true-home/neutral gap grew not because true-home rose (it is flat) but because neutral-venue advantage collapsed over time.",
 "method": "Venue-control decomposition: matches are split on the real `neutral` flag into true-home (neutral=False) vs neutral-site (neutral=True), then goal difference and win/draw/away rates are compared within era and tournament type. The neutral split is the natural control -- not a random assignment.",
 "source_parquet": "data/domains/soccer_intl/results.parquet",
 "observation_window": {
  "first_date": "1872-11-30",
  "last_date": "2026-06-16",
  "n_matches_played": 49425,
  "note": "the full committed international-results corpus (~150 years, 1872-2026), not a rolling cache"
 },
 "venue": {
  "true_home": {
   "n": 36350,
   "home_win_rate": 0.5074,
   "draw_rate": 0.2286,
   "away_win_rate": 0.264,
   "goal_diff": 0.6744
  },
  "neutral": {
   "n": 13075,
   "home_win_rate": 0.4418,
   "draw_rate": 0.2242,
   "away_win_rate": 0.3339,
   "goal_diff": 0.3007
  }
 },
 "hfa_effect": {
  "goal_diff": 0.3737,
  "home_win_rate": 0.0656
 },
 "by_era": [
  {
   "era": "pre-2000",
   "true_home_goal_diff": 0.6743,
   "neutral_goal_diff": 0.4556,
   "effect_goal_diff": 0.2187,
   "n_true_home": 18235,
   "n_neutral": 5827
  },
  {
   "era": "2000+",
   "true_home_goal_diff": 0.6745,
   "neutral_goal_diff": 0.176,
   "effect_goal_diff": 0.4985,
   "n_true_home": 18115,
   "n_neutral": 7248
  }
 ],
 "by_tournament_type": [
  {
   "bucket": "Friendlies",
   "n": 18388,
   "true_home_n": 15724,
   "true_home_goal_diff": 0.5648,
   "neutral_n": 2664,
   "neutral_goal_diff": 0.1779,
   "effect_goal_diff": 0.3869
  },
  {
   "bucket": "Qualifiers",
   "n": 15928,
   "true_home_n": 14264,
   "true_home_goal_diff": 0.7592,
   "neutral_n": 1664,
   "neutral_goal_diff": 0.1358,
   "effect_goal_diff": 0.6234
  },
  {
   "bucket": "Finals & continental",
   "n": 15109,
   "true_home_n": 6362,
   "true_home_goal_diff": 0.7553,
   "neutral_n": 8747,
   "neutral_goal_diff": 0.3694,
   "effect_goal_diff": 0.3859
  }
 ],
 "travel_leg": {
  "testable": false,
  "note": "results.parquet carries city/country strings but no coordinates; a travel-distance residual leg is NOT_TESTABLE from committed data and is deliberately not estimated."
 },
 "confounds": [
  "neutral games are non-random (concentrate in tournament finals -- 8747 of 13075)",
  "crowd is never directly observed (NOT_TESTABLE)",
  "no strength-of-schedule / team-quality adjustment (opponent-raw)",
  "draws included in win-rate base"
 ],
 "receipt": {
  "committed_ledger": "scripts/platformkit/analytics_showcase/out/mechanism_ledger_export.json",
  "mechanisms": [
   "home_advantage_neutral_vs_true_goal_diff",
   "home_advantage_neutral_vs_true_win_rate",
   "home_advantage_neutral_split_half_by_era"
  ],
  "verdict": "CONFIRMED_LOCAL"
 }
}