Library/Reading the Count: Prediction Markets and Brazil's 2026 Presidential Election
MicrostructureResearch Paper
Reading the Count: Prediction Markets and Brazil's 2026 Presidential Election
Raphael Coelho·October 30, 2026·Academic Paper
“their prices implied about four times the live projection's uncertainty”
Why It's Worth Reading
Brazil's runoff night gave an exact test of how fast markets absorb a public count: a live projection gave Lula 0.998 at 19:15 with 1.6% of sections tallied, while Kalshi and Polymarket only reached 0.90 at 20:24 with 46% counted. Their prices implied about four times the projection's uncertainty. Takers who bought Lula at 0.78 earned 4 to 18 cents per Kalshi contract after fees — zero against a state-level extrapolation.