Provides sophisticated yet easy to understand ranking system with minimum changes to the system. Elo ranking system is heavily used in tournaments, player rankings in chess, sports, leader boards, multiplayer games, ranking of test questions, tasks etc.

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acts_as_elo is very easy to use

1. Install: gem install acts_as_elo
2. Add include Acts::Elo and acts_as_elo
3. Call any of the 3 methods: elo_win!, elo_lose! and elo_draw!

class Player
  include Acts::Elo
  acts_as_elo
end

bob, jack = Player.new, Player.new
bob.elo_rank # => 1200
jack.elo_rank # => 1200

bob.elo_win!(jack)
bob.elo_rank # => 1215
jack.elo_rank # => 1985

Released under the MIT License. See the LICENSE file for further details.