24 historical questions. Set your probability. See your Brier score. Learn where your confidence goes wrong.
What is calibration? A forecaster is well-calibrated when things they say are 70% likely actually happen 70% of the time. Being calibrated is a learnable skill.
Brier score: (your probability − actual outcome)². Lower is better. Always saying 50% gives you 0.25. Good forecasters score below 0.15. Superforecasters reach 0.06–0.08.
How to play: Each question has a known historical outcome (Yes or No). Set your probability that the answer is Yes, then submit. 24 questions across markets, geopolitics, elections, and technology.