{
  "title": "Y-Chromosome Lineage Variation Across Cabo Verde: Island-Level Frequencies and the Effect of Weighting",
  "creator": "Badiu Nation Research Project",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "version": "2026-09-13",
  "article": "https://www.badiunation.page/essays/ydna-island-weighting",
  "islandDefinition": "Reported birthplace of the participant's paternal grandfather; not current residence or sample-collection location.",
  "weightDefinition": "Specified analytical scenario, not validated census or national population weights. Weights sum to 1.",
  "countUnit": "Participants assigned once to one island and one reporting haplogroup category",
  "collectionPeriod": "March 2023 to February 2025",
  "sampleSize": 1257,
  "categories": ["A1a", "E1a", "E1b1a", "E1b1b", "E2b", "R1b", "I2a", "G2a", "J", "T"],
  "rows": [
    {"island": "Santiago", "n": 417, "scenarioWeight": 0.571, "counts": [26, 72, 265, 48, 6, 0, 0, 0, 0, 0]},
    {"island": "São Vicente", "n": 199, "scenarioWeight": 0.156, "counts": [3, 8, 34, 28, 2, 96, 9, 3, 14, 2]},
    {"island": "Santo Antão", "n": 103, "scenarioWeight": 0.070, "counts": [1, 4, 27, 23, 0, 39, 1, 1, 5, 2]},
    {"island": "Fogo", "n": 107, "scenarioWeight": 0.064, "counts": [1, 8, 6, 27, 0, 48, 2, 6, 9, 0]},
    {"island": "Sal", "n": 111, "scenarioWeight": 0.064, "counts": [5, 14, 38, 6, 1, 33, 4, 1, 7, 2]},
    {"island": "Boa Vista", "n": 82, "scenarioWeight": 0.030, "counts": [0, 1, 28, 19, 0, 27, 1, 3, 3, 0]},
    {"island": "São Nicolau", "n": 89, "scenarioWeight": 0.022, "counts": [4, 8, 26, 5, 0, 40, 3, 0, 3, 0]},
    {"island": "Maio", "n": 76, "scenarioWeight": 0.013, "counts": [6, 14, 36, 6, 1, 12, 1, 0, 0, 0]},
    {"island": "Brava", "n": 73, "scenarioWeight": 0.010, "counts": [0, 16, 5, 22, 0, 23, 4, 1, 2, 0]}
  ],
  "notes": [
    "Counts are aggregate study reporting categories, not individual genetic records or downstream subclade calls.",
    "Counts arrays use the order in categories. Frequencies and differences are calculated before rounding.",
    "A zero means no assignment in this sample, not proven population absence.",
    "Combined haplogroup categories are not genome-wide ancestry proportions."
  ]
}