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NEW: Prediction Markets API

One REST API for all prediction markets data

Probability Calibration

Probability calibration is the process of checking whether a prediction market’s probabilities match real-world outcomes. It measures how well stated probabilities reflect actual event frequencies.
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Probability calibration evaluates whether prediction markets assign probabilities that truly correspond to how often events occur. For example, if events priced at 40% happen roughly 40% of the time, the market is considered well-calibrated. This comparison helps reveal whether traders are generally cautious, overconfident, or well-aligned with reality.

Prediction markets generate continuous probability data throughout an event’s life cycle. After many markets resolve, analysts compare predicted probabilities with outcomes to see where forecasting strengths and weaknesses lie. This produces structured prediction markets data that reflects long-term forecasting quality rather than just individual wins or misses.

Well-calibrated markets inspire trust. They show that probability values mean what they’re supposed to mean. Poor calibration, on the other hand, signals potential issues in incentive structures, market design, liquidity, or information flow. Improving calibration helps platforms produce more reliable forecasting signals.

Probability calibration shows whether prediction markets provide trustworthy probabilities. It turns raw prediction markets data into insights about accuracy, bias, and forecasting effectiveness.

Probability calibration matters because prediction markets aim to output meaningful probabilities, not just rankings or guesses. Without calibration, users cannot interpret the numbers confidently. Calibration reveals whether the market systematically overestimates or underestimates outcomes. This helps platforms refine design choices and ensures prediction markets data remains credible for forecasting, planning, and analysis.

Analysts typically group events by predicted probability buckets—such as 10%, 30%, 60%, or 90%—and compare those buckets to how often events actually occurred. They use tools like calibration curves and Brier Scores to quantify accuracy. Large gaps signal miscalibration, while close alignment indicates strong forecasting. This structured evaluation turns prediction markets data into actionable insights for improving market performance.

Probability calibration highlights overconfidence, underconfidence, liquidity problems, or unclear market design. Analysts can identify which probability ranges perform well and which consistently miss the mark. They can compare calibration across event types, industries, or time periods to diagnose where forecasting is strongest. These insights help teams strengthen forecasting systems and improve future prediction markets data quality.

A platform reviews a collection of markets forecasting whether tech companies will announce new product features by specific deadlines. Analysts compare predicted probabilities with actual launch outcomes. They discover that markets priced between 70% and 80% were accurate, but lower-probability forecasts were too pessimistic—revealing a calibration issue that needs attention.

Probability calibration requires comprehensive historical data, including predicted probabilities and final event outcomes. FinFeed's Prediction Markets API provides this structured prediction markets data—making it easy for developers to calculate calibration metrics, generate calibration curves, and evaluate long-term forecasting accuracy across categories.

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