{
  "article_no": 63,
  "title_draft": "2車ラインと3車ライン、番手の連対率はどう違う？",
  "db": "keirincraft",
  "as_of": "2026-08-17",
  "period": "2021-06-22 to 2026-08-17",
  "population_definition": "keirin_races.status='finished' AND is_girls=false AND num_cars=7 (男子7車立て・確定レース)",
  "by_line": [
    {"line_len": 2, "line_pos": 1, "role": "先頭", "n": 148799, "win_rate": 15.63, "place2_rate": 27.97, "place3_rate": 40.10},
    {"line_len": 2, "line_pos": 2, "role": "番手", "n": 148799, "win_rate": 8.55, "place2_rate": 21.15, "place3_rate": 34.40},
    {"line_len": 3, "line_pos": 1, "role": "先頭", "n": 106051, "win_rate": 27.01, "place2_rate": 46.05, "place3_rate": 58.45},
    {"line_len": 3, "line_pos": 2, "role": "番手", "n": 106051, "win_rate": 21.91, "place2_rate": 45.92, "place3_rate": 61.02},
    {"line_len": 3, "line_pos": 3, "role": "3番手", "n": 106051, "win_rate": 2.34, "place2_rate": 9.65, "place3_rate": 29.89}
  ],
  "note_on_n_diff_from_no62": "no62取得時(同日午前)はn=106,049だったが、本クエリ(同日午後)ではn=106,051。当日中にレースが確定し2件増えたための差。両方とも2026-08-17基準の実測値。",
  "baseline_7cars_equal": 14.29
}