How do I turn it on or off?
Disable Elo Ratings in:
Setup > Statistics Setup > Game Formats > Settings
When enabled:
All-time and Season ratings are shown on the stat leaders page
Upcoming matches show a probability grid of who is most likely to win each matchup
A graph of all-time and season ratings through time are shown on the player page
Rating adjustments for each game are shown on the player page
Elo ratings are calculated behind the scenes and there maybe a 5 minute lag.
What is the Elo rating system?
The Elo rating system automatically assigns a numerical rating to each player, which represents their skill level.
When two players compete against each other, the outcome of the game affects their ratings.
If a lower-rated player defeats a higher-rated player, their rating will increase more significantly compared to if they had won against a lower-rated player.
Conversely, if a higher-rated player wins against a lower-rated player, their rating will increase by a smaller margin.
The Elo rating system takes into account the ratings of both players involved in a game, as well as the expected outcome based on their respective ratings.
If a player with a higher rating wins against a player with a lower rating, the rating change will be smaller than if the lower-rated player had won.
The magnitude of the rating change depends on the difference in the players' ratings and the K-Factor.
The K-factor represents the maximum potential rating adjustment for each game.
Elo rating example
Let's assume Player 1 has a rating of 1400 and Player 2 has a rating of 1600, with a K-factor of 32.
To calculate the expected outcome, we use the following formula:
Expected outcome for Player 1 = 1 / (1 + 10^((Player2Rating - Player1Rating)/400))
Expected outcome for Player 2 = 1 / (1 + 10^((Player1Rating - Player2Rating)/400))
In this case:
Expected outcome for Player 1 = 1 / (1 + 10^((1600 - 1400)/400)) = 1 / (1 + 10^(200/400)) = 1 / (1 + 10^0.5) = 1 / (1 + 3.162) = 1 / 4.162 = 0.240
Expected outcome for Player 2 = 1 - 0.240 = 0.760
Let's say Player 1 wins the match. The actual outcome is 1 for Player 1 and 0 for Player 2.
To calculate the rating adjustment for each player, we use the following formula:
Rating adjustment = KFactor * (Actual outcome - Expected outcome)
For Player 1: Rating adjustment = 32 * (1 - 0.240) = 32 * 0.760 = 24.32
For Player 2: Rating adjustment = 32 * (0 - 0.760) = 32 * -0.760 = -24.32
After the match, the updated ratings would be:
Player 1 = 1400 + 24.32 = 1424.32
Player 2 = 1600 - 24.32 = 1575.68
So, when rounded, Player 1's rating increases to 1424, and Player 2's rating decreases to 1576 based on their performance and the K-factor.
Note: For doubles calculation we use the average Elo rating of both players in the team.
We do not adjust Elo ratings for triples teams and larger teams.