Our goal is to make a rating that accurately represents the true skill level of every team and explains how their in-game actions affect their position in the rankings. With that in mind, allow us to explain the inner workings of our rankings.
We took a normal distribution as the basis for our formula.
For a normal distribution, the values which differ from the mean by a number smaller than one standard deviation constitute 68.27% of the population. At the same time, the values which differ from the mean by two standard deviations constitute 95.45%, and three standard deviations – 99.73%.
Every new team starts with a rating of 3500, and its initial deviation is 1000. This means that the estimated team’s rating ranges somewhere between 2500 and 4500. After each game, the team moves right or left on the rating axis depending on the result, and its deviation decreases.
A team with a rating of 3500 and a deviation of 1000 wins its first game and gets a new rating of 3500 + X and a new deviation of 1000 - Y. This means the new team’s rating ranges from 2500 + X - Y to 4500 + X - Y.
The more games the team plays, the lesser is the deviation, since with every new game, we are more certain in which rating interval the team is placed.
To be added to the rankings, you have to play at least 20 games in Professional or Premium leagues or on our Tournament Platform in a 5v5 mode. The last game must have been played no later than 2 months ago.
Apart from victory or defeat, there are various stats that also influence the rating:
We analyzed 64377 matches played in the last 2 years and figured out the average match duration and the difference in gold and XP.
Distribution of matches by duration
Distribution of matches by gained XP
Distribution of matches by difference in gold
We created a formula that adds or takes away bonus rating points depending on how convincing the victory was: the shorter the game was or the bigger the difference in gold and XP, the more convincing the victory is. In actuality, the mathematics are a little bit more complicated, but you get the gist.
The current ranking system rates teams quite objectively according to their results and with no inflation. But, there are still a couple of things we want to change:
Stay tuned for more updates!