Can a good forecast still lose?
Constantly. A well-priced 65% call resolving No is normal, not a mistake.
Edge
Calibration: are you actually good, or just lucky?
Calibration is the boring superpower, being right about how uncertain you are, measured across many calls instead of one lucky hit.
forecasting calibrationbrier score explainedam i a good forecasteroverconfidence in betting
The short version
You are calibrated when the things you call 70% actually happen about 70% of the time. Group your calls into buckets, check each bucket against reality, and you will see exactly where you are overconfident. A Brier score puts one number on it. Most people are way too sure of themselves, and the book bills them for it.
Why it matters
A single win proves nothing; even a coin flip wins half the time. Calibration is how you tell a repeatable edge from variance wearing a confidence costume. It is also the fastest cure for the most expensive habit in this game: betting big on a 90% read that was really a 60%.
How to check yourself
- Pull every market you called ~60% and see how many hit
- Compare your number to the price right before resolution
- Sort outcomes by your confidence bucket and look for the leaks
The mechanics
Sample sizeCalibration needs volume. Ten calls is a story; a few hundred is data.
Probability bucketsGrouping by confidence level is what exposes systematic over- or under-confidence.
Brier thinkingA proper scoring rule rewards honest probabilities, not lucky binary wins.
PostmortemsSeparate bad luck from bad process. Only one of them is fixable.
FAQ
What is overconfidence, exactly?
Stating 90% when reality is 65%. It feels sharp and it slowly empties the account.
Do I need to compute a Brier score?
Not to start. Eyeballing your buckets against outcomes gets you most of the insight for none of the effort.