FAF started using a division-based system for leaderboards instead of the TrueSkill ratings in 2022. This article explains why this change happened.
TrueSkill is a very good system to quickly determine players' performance, which is needed to provide balanced matches. This system relies on statistical models which makes it somewhat complicated to understand, especially without appropriate mathematical background knowledge.
As the system factors in not only the rating mean but also the uncertainty of a player's rating, it regularly leads to situations where people are surprised by the rating changes after a game. (People in the team getting a different amount of points, people losing or gaining a rating after a draw, etc.) This is not a flaw in the system, but it creates a bad user experience.
Additionally, people regularly ask for rating resets or decays because they feel they can’t perform on their original level anymore after a long break or because people that haven’t played in years are still at the top of the leaderboard. Many other online games circumvent these problems by building another layer on top that is easier to understand and works in seasons that provide a periodic reset of the leaderboard while the matchmaker rating – TrueSkill in our case – can work in the background undisturbed.
So FAF decided to build a similar system.
Matchmaking is still based on TrueSkill for fair games and the TrueSkill calculation still happens in the background as usual. Several divisions got set up that are tied to a TrueSkill rating range. Before putting a player in a division there is a placement phase of 10 games. This gives TrueSkill some time to determine the rating for new players.
Subdivisions functionally behave exactly like divisions. The player will then be placed in the appropriate subdivision based on his TrueSkill rating. Specifically, 100 points lower to have a soft reset at the season start and to provide the opportunity to climb. The starting points in the division are based on his relative position in the division (many if close to the rating ceiling, less if closer to the rank rating of the division).
Generally, you gain one point for a win and drop one point for a loss. A draw leads to no point change. When you have a higher rating than the rating range of your current division, then you will gain two points for a win. Similarly, if you have a lower rating than the rating range of your division, then you will drop two points for each loss. This makes sure that all players generally are in the division that correlates to their rating, ensuring that the division gives useful info about a player’s skill.
Players will automatically rank up to the next (sub)division if they exceed the point maximum of the current division. They will then start with 2 points in the next division to prevent instant de-ranking. Similarly, they will de-rank if falling under 0 points and will then start with 2 points under the division point maximum to prevent an instant up-rank.
At the end of a season that lasts three months, the leaderboard will be reset and people have to play placement games again. This provides the „rating“ resets for inactive players and makes sure that the leaderboard stays up to date. To make the placement games less of a drag, you will only need to play three games when you were already placed in an earlier season.
| Division | Intended TrueSkill Rating (µ-3sigma) | Point maximum | |
| Grandmaster | 2000+ | 100 | |
| Master | I | 1915+ | 10 |
| II | 1830+ | 10 | |
| III | 1745+ | 10 | |
| IV | 1660+ | 10 | |
| V | 1575+ | 10 | |
| Diamond | I | 1490+ | 10 |
| II | 1405+ | 10 | |
| III | 1320+ | 10 | |
| IV | 1235+ | 10 | |
| V | 1150+ | 10 | |
| Gold | I | 1065+ | 10 |
| II | 980+ | 10 | |
| III | 895+ | 10 | |
| IV | 810+ | 10 | |
| V | 725+ | 10 | |
| Silver | I | 640+ | 10 |
| II | 555+ | 10 | |
| III | 470+ | 10 | |
| IV | 385+ | 10 | |
| V | 300+ | 10 | |
| Bronze | I | 215+ | 10 |
| II | 130+ | 10 | |
| III | 45+ | 10 | |
| IV | -40+ | 10 | |
| V | -40 and lower | 10 | |