What is Elo?
Elo, a widely used rating system in competitive online games, sports, and board games, was originally developed as a more effective way to rank chess players. It serves as a tool to measure the skill levels of players, comparing their relative proficiency in a specific game. This numerical rating system is a key component in determining fair and balanced matches.
How is Elo used?
The difference in ratings between two players predicts the outcome of a match. Two players with equal ratings who play against each other are expected to score an equal number of wins. A player whose rating is 100 points greater than their opponent’s is expected to score 64%; if the difference is 200 points, then the expected score for the stronger player is 76%.
A player’s Elo rating is a number that may change depending on the outcome of the games that are rated. After every game, the winning player takes points from the losing one. The difference between the ratings of the winner and loser determines the total number of points gained or lost after a game. If the higher-rated player wins, only a few rating points will be taken from the lower-rated player. However, many rating points will be transferred if the lower-rated player scores an upset win. The lower-rated player will also gain a few points from the higher-rated player in the event of a draw. This means that this rating system is self-correcting. In the long run, players whose ratings are too low or too high should do better or worse correspondingly than the rating system predicts and thus gain or lose rating points until the ratings reflect their true playing strength.
Elo ratings are comparative only and valid only within the rating pool in which they were calculated, rather than being an absolute measure of a player’s strength. You can’t compare Elo ratings from different games or leagues.
While Elo-like systems are widely used in two-player settings, variations have also been applied to multiplayer competitions.
How Elo helps with AI
Google Deepmind uses Elo to train its models designed for games such as AlphaGo, MuZero, and AlphaStar. It also uses leagues to cultivate different capabilities that can then be promoted into other leagues. Their use of Elo has become one of the key ways to assess and monitor LLM performance.
One of the benefits of the Elo system is its ability to offer a fair and balanced matchmaking experience, ensuring that players are pitted against opponents of similar skill levels. By using Elo ratings, gaming platforms can enhance the overall gaming experience by creating more competitive and engaging matches.
The Elo system plays a role in motivating players to enhance their skills and aim for higher ratings. This element of progression and motivation adds depth to the gaming experience.
