Elo rating system

System for rating game players

The Elo rating system is a method for calculating the relative skill levels of players, originally designed for rating chess players. It is a special case of the Bradley–Terry model. The Elo system was invented as an improved chess rating system over the previously used Harkness rating system and has since been adapted for use in other zero-sum games and sports, including tennis, association football (soccer), American football, baseball, basketball, pool, various board games and esports.

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