How this is measured
- For every settled contract that had a reference probability, we record the reference and the market price 24 hours and 1 hour before the market closed, and whether the contract settled yes or no.
- The market price is the last trade, else the midpoint of the bid and ask. A contract with no quote at a checkpoint is skipped for both sides and counted in the last column.
- The Brier score is the average squared difference between the forecast and the result (1 for yes, 0 for no). Lower is better: 0 is perfect, and always saying 50% scores 0.25.
- "Closer" is the share of contracts where that side's forecast was nearer the result; the rest were ties.
- Calibration groups forecasts into 10 bands of 10 points and plots the average forecast in each band against how often those contracts settled yes. A well calibrated forecast sits on the diagonal.
- An event counts once even when it has several contracts (one per temperature bracket or price level), because its contracts settle together. Scores are recomputed daily.
A reference that scores worse than the market is a finding about the reference, and it is shown the same way. These figures describe past data, not future results, and none of this is a recommendation to trade. Not financial advice. See the methodology and the responsible trading page.