# Brazil Election Polls vs Polymarket Odds: What the Numbers Mean

Scope checked against the publication dated 25 October 2026.

Selected calculations checked in Lean. The empirical study is not formally proved.

Calculation and displayed-value checks:

- The two survey response shares add to 100%. (`brazil_election_2026_polls_vs_prediction_markets_1`; arithmetic).
- The two model probabilities add to 100%. (`brazil_election_2026_polls_vs_prediction_markets_2`; arithmetic).
- The two contract checkpoints add to 99.7 cents, not an assumed normalized probability distribution. (`brazil_election_2026_polls_vs_prediction_markets_3`; arithmetic).
- Displayed Flávio Bolsonaro values lie between 0 and 100 in short-answer-chart. (`brazil_election_2026_polls_vs_prediction_markets_4`; displayed-value-domain).
- Displayed Lula values lie between 0 and 100 in short-answer-chart. (`brazil_election_2026_polls_vs_prediction_markets_5`; displayed-value-domain).

The calculations retain the separate vote-share, model-probability and contract-price denominators; no mapping from one to another is proved.

Outside the proof:

- Authenticity, completeness and accuracy of source observations.
- Data collection, sampling, classification, bootstrap intervals and causal inference.
- Current prices, policy, legal status, allegations, product claims and future outcomes.
- Production code correctness, execution, available liquidity and profitability.

[Machine-readable scope and exact input locations](brazil-election-2026-polls-vs-prediction-markets.json). [Lean calculations](../LibraryChecks.lean). [Mathematical definitions](../ResearchModels.lean). [Verification record](../verification.json). [Complete package](../proofs.zip).

Body SHA-256: `f73354044260f439d7e52f5e3aa88ec7d096c278adc5c727cd525bfe5c918c74`. Source observations are premises, not conclusions of the proofs.

25 Oct 2026: the body hash now leaves out the photograph block (image), as it already left out sources and updatedAt. The scope is unchanged. Previous body SHA-256: 82f29bd6cead52a7ca45d3eda4f2280cec89d0a69aef19c4c9bdf94d56f62dfc.