{
  "schemaVersion": "vultax-public-research-data-v1",
  "articleUrl": "https://vultax.com/research/brazil-election-2026-polls-vs-prediction-markets",
  "datasets": [
    {
      "title": "The same pollster and denominator, a later fieldwork window",
      "columns": [
        {
          "name": "Candidate",
          "unit": null
        },
        {
          "name": "13–14 October",
          "unit": null
        },
        {
          "name": "20–22 October",
          "unit": null
        }
      ],
      "rows": [
        [
          "Flávio Bolsonaro",
          "51%",
          "50%"
        ],
        [
          "Lula",
          "49%",
          "50%"
        ]
      ],
      "measurementContext": "Datafolha rounded valid-vote shares; fieldwork dates, not publication times. The diagram uses these same four values.",
      "sources": [
        {
          "label": "Datafolha: national presidential runoff survey",
          "url": "https://datafolha.folha.uol.com.br/eleicoes/2026/10/flavio-bolsonaro-pl-tem-47-e-tem-empate-tecnico-com-lula-pt-que-aparece-com-45.shtml",
          "note": "Released 16 October 2026; fieldwork 13–14 October; TSE BR-00466/2026. Pollster's primary release."
        },
        {
          "label": "Polymarket: Brazil Presidential Election",
          "url": "https://polymarket.com/event/brazil-presidential-election",
          "note": "Public page checked 19 October 2026. Displayed Yes offers: Flávio Bolsonaro 77¢, Lula 24¢. A page observation, not a guaranteed fill."
        },
        {
          "label": "Datafolha: 20–22 October national runoff survey",
          "url": "https://datafolha.folha.uol.com.br/eleicoes/2026/10/flavio-bolsonaro-pl-tem-47-e-tem-empate-tecnico-com-lula-pt-que-aparece-com-46.shtml",
          "note": "BR-09709/2026; 2,520 interviews, 154 municipalities. The pollster’s own release."
        },
        {
          "label": "Datafolha: complete original report",
          "url": "https://media.folha.uol.com.br/datafolha/2026/10/23/xruy9kxbaieozsbhp0lxbvdrv6cvlf5iuxgfkw04tre.pdf",
          "note": "Methodology on PDF page 2; published valid-vote chart on page 9. Read and visually checked 24 October."
        },
        {
          "label": "Vultax: preserved Brazil room observation",
          "url": "https://app.vultax.com/api/rooms/brazil-election-2026",
          "note": "The article uses the retained 24 October 13:37:43 UTC response. This endpoint itself keeps updating."
        },
        {
          "label": "Vultax: forecast evidence and recorded history",
          "url": "https://app.vultax.com/api/forecast-proof/brazil-election-2026",
          "note": "The article uses the retained 24 October 13:37:41 UTC model. Its 11 then-recorded observations are one election, not 11 independent forecasting successes."
        },
        {
          "label": "Selected arithmetic checked in Lean 4.35.0",
          "url": "https://vultax.com/datasets/research-proof-library-2026-10-25/articles/brazil-election-2026-polls-vs-prediction-markets.md",
          "note": "Selected exact-rational calculations and displayed-value consistency checks, checked by Lean 4.35.0, Lean kernel replay and Nanoda. Not a proof of the underlying observations, statistical conclusions, legal claims or production code."
        },
        {
          "label": "Per-article scope records and Lean package",
          "url": "https://vultax.com/datasets/research-proof-library-2026-10-25/README.md",
          "note": "Dated per-article scope records, Lean source, frozen permitted public inputs, checker logs and a reproducible ZIP. Covers only the scope stated in each record, not the whole study."
        }
      ],
      "measurement": {
        "kind": "observed",
        "temporalCoverage": "2026-10-13/2026-10-22",
        "population": "Datafolha valid-vote estimates in two distinct polling waves",
        "methodology": "Retained published rounded shares; no renormalisation, national result or win probability inferred."
      },
      "id": "two-datafolha-waves-table",
      "kind": "published-table",
      "description": "Datafolha’s 20–22 October poll and a dated market snapshot answer different questions. Read vote shares, win probabilities and the model’s limits.",
      "articleUrl": "https://vultax.com/research/brazil-election-2026-polls-vs-prediction-markets",
      "sectionUrl": "https://vultax.com/research/brazil-election-2026-polls-vs-prediction-markets#two-datafolha-waves",
      "publishedAt": "2026-10-19",
      "modifiedAt": "2026-10-25",
      "version": "d1bd21846d178970a515cabff3fed99ec64b93e09c08f033ee425eb68a0408bc",
      "isLive": false,
      "limitations": "Published research snapshots and calculations; these exports do not contain current quotes or live account data. Observation windows and populations are stated in the source captions and methodology. Missing metadata is unknown, not zero. The 24 October checkpoint preserves its stated fieldwork, model and market clocks. Earlier examples retain their original dates. The polling model is experimental and has no validated election track record. Official election results and venue settlement remain separate; no outcome or trading return is claimed.",
      "downloads": {
        "json": "https://vultax.com/research/brazil-election-2026-polls-vs-prediction-markets/data.json?dataset=two-datafolha-waves-table",
        "csv": "https://vultax.com/research/brazil-election-2026-polls-vs-prediction-markets/data.csv?dataset=two-datafolha-waves-table"
      }
    }
  ]
}