Glossary · Phase 2 · Math, when you need it
Elo rating
A rating updated after every game: the winner gains points in proportion to how surprising the win was. A 400-point gap means 10-to-1 odds.
Try it now
The curve is an S shape: small gaps matter a lot near even, and huge gaps approach certainty but never reach it.
Learn it properly
Ranking from head-to-head results · Elo updates, Bradley-Terry strengths, and how model leaderboards turn votes into ratings. About 25 minutes.
Other terms from the same lesson
- Bradley-Terry model: A way to turn many "A beat B" judgments into one strength score per item, so you can predict how often any item beats any other.
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