Update of the ranking system of the AoW3 league of the Battlefield (Community)

The way ranking points are gained and lost as well as the page explaining the ranking have been updated. The changes make the ranking easier to understand, reward players more for winning games involving many participants and should remove the clutter of players around 1000 points.

An Article by Hiliadan

The Battlefield is a community website for AoW3 and other games such as Civilization 5 and 6. It provides many services for the AoW3 online community such as:

Since the 1st November 2016, the ranking system is being updated together with its explanations, in order to make the system more transparent, simple and fair. Two basic ideas lead the ranking system, which is based on the Elo ranking system (used in Chess for instance): better players should have a higher ranking (which is quite obvious!) and new players should be able to climb the ranking fast if they are good, so that the ranking is quite dynamic and players are motivated to report their games.

The general ranking as of November 10th

The new system works as follow [please note that it is not yet fully effective and that points for game since 1st November will probably change in the future until the system is fully stabilized, sorry for the inconvenience]:

The system used for the AoW3 league is the "Elo Point System for FFA Leagues (with start bonus)"

About the Point System
A good ranking needs a good and fair Point System to rank and classify players. The ranking system on the Battlefield is based on the Elo system (see below).
Players are sorted in descending Points order.

Which ranks can be achieved?
Beginner: 700-1000 points
Veteran: reached more than 1000 at least once (but may have gone back below 1000)
Elite: the top 30% of Veteran players
Master: the top 10% of Veteran players

Starting conditions
Players start with 700 points and are listed in the ranking.

Start Bonus
Beginners (under 1000 points) get a bonus: their point gains are doubled and they do not lose points. New players can thus climb the ranking faster.

The ranking points are based on the Elo system
Each player get a number of points based on the Elo system (see Wikipedia for more information on the Elo system). When players start, they get 700 points (see "Starting conditions" above).
The Elo system is based on the K-Number, the Difference number and the Result number, detailed below, for people wanting more details.
After each match, the change in ranking for each player is calculated by a formula (see details below): Change = (Result - Difference) x K

This number is the multiplier applied to the points gained or lost: a higher K-Number means more points won or lost. The K number varies according to the number of games played or current points. Its values are:

  • Less than 10 games played: 25

  • More than 10 games and less than 1400 points: 20

  • More than 10 games or 1400 points: 15

Difference number
A Difference number is calculated for each player involved in a match. For each player, its Difference is the subtraction of his ranking points with the ranking points of others.
If Player 1 has 1000 ranking points and Player 2 has 1600 ranking points.
The Difference number for Player 1 is 1000 - 1600 = -600
The Difference number for Player 2 is 1600 - 1000 = 600

Result number
This number represents the result in the game assessed: 1 stands for victory, 0 for defeat and a formula is used to calculate the result number in case of a game with more than 2 players: Result number = 1 * (total number of players in the game - position achieved by the player assessed) / (total number of players in the game - 1)

Player 1 is #1, Player 2 is #2 and Player 3 is #3. Their respective Result numbers are:
Player 1 = 1 (win)
Player 2 = 1 * (3 - 2) / (3 - 1)= 0,5
Player 3 = 0 (lost)

Expectation number
The Expectation number represents the probability for a player to win the game: better players have a greater Expectation to win. The Expectation number is computed using the formula designed by Professor Arpard Elo (who gave his name to the Elo system).

Formula: Expectation number = 1 / (1 + 10^(- Difference number / 400))

If Player 1 has 1800 ranking points and Player 2 has 2400 ranking points.
Then the Expectation number for Player 1 is:
1 / (1 + 10^(- (-600) / 400))
That is to say, it is equal to 0,01958: Player 1 has a probability of winning of 1.958%.

Player 2 = 1 / (1 + 10^(- 600 / 400))
That is to say, it is equal to 0,98042: Player 2 has a probability of winning of 98.042%.

The Change is the number of points the player will gain or lose. It depends on the Expectation number, the Result number and the K-Number, following this formula:
Change = (Result - Expectation) x K

If we keep the same figures as in the example in the previous section:
Change for Player 1 = (1 - 0,01958) x 25 = 24.511
Change for Player 2 = (0 - 0,98042) x 15 = -14 ,706

Addition / subtraction
In games with more than 2 players, the higher the position of a player at the end of the game (being 1st is the highest position achievable obviously), the more points he will add to his ranking points.
Conversely, when a player finishes at the bottom of a game with many players, many points will be substracted from his ranking points.

If we have the following positions at the end of a game: #1 - Player A; #2 - Player B; #3 - Player C and the change calculated between each players is as follow:
A vs B = 30 points
A vs C = 20 points
B vs C = 15 points
Then the changes will be:
Player A: 30 + 20 = 50
Player B: -30 + 15 = -15
Player C: -15 + -20 = -35

Team relationships:
When several players are in the same team, the points they gain will be reduced by applying the following formula:
Points * ((Total number of players – Number of team mates, excluding oneself) / Total number of players)

Two teams of two with Player A & Player B (Team 1) vs Player C & Player D (Team 2)
Team 1 = 50 points for Player A ==> 50 * ((4-1)/4) ==> 50 * 3 / 4 = 37,5
Team 1 = 40 points for Player B ==> 40 * ((4-1)/4) ==> 40 * 3 /4 = 30
Team 2 = -50 points for Player C ==> -50 * ((4-1)/4) ==> -50 * 3 / 4 = -37,5
Team 2 = -40 points for Player D ==> -40 * ((4-1)/4) ==> -40 * 3 /4 = -30

What to do after the end of a game
The winner or one of the player in the game will report the game at the related Battlefield page!
All players (and the Admin) will then get an email Report about the game. Everyone can contest and delete the report if it is not correct or contact the Admin, who will then investigate it and maybe change the report and solve the issue. Players can also rate their opponents and the game from the report page.

Computing of Ranking Points
Every game reported in the FFA league will influence the ranking. All the players who played a game will get point changes!

If we go back to our example:
Player 1 won 25 points which means his updated ranking points will be 1000 (previous ranking points) + 25 (earned during the match) = 1025 points.
Player 2 lost 15 points, and his updated ranking points will be: 1600 (previous ranking points) - 15 (earned during the match) =1585 points.

In a report, the following values are displayed:
- Points: the points gained or lost
- Extra Points: the bonus points (generally due to the x2 bonus for Beginners)
- Missed Points: the difference between the points a player could have gained if he (or his team) had won the match and what he actually gained (or lost). The Missed Points can be significant if a player loses the match and loses points (e.g. if winning would have brought him 20 points and he lost and his points decreased by 15, his Missed Points value is 20 - ( -15) = 35
- Game Value: it indicates the value of the players involved, the interest of the game. It is calculated by taking the square root of the sum of the ranking points of all the players. Typically, a Game Value of 20 is relatively low and is generally a duel, whereas a Game Value of 90 or more indicates a very big game with 8 Veteran players.

Further Rules / Exceptions

Quitter Penaly -20 points

The main changes compared to the old system (pre-1st November) are:

  • Veterans can now fall below 1000 points (in the past there was a floor of 1000 points and Veterans could not go below it)

  • The K-value does not vary according to the number of players involved (before K was equal to 25*6/[number of players involved] so duels had a K of 75 and 8 players game a K lower than 25).

The ranking points gained or lost with matches which occurred before 1st November should remain unchanged.

The ranking page will be updated with new icons and information about the status (Beginner, Veteran, Elite, Master) of each player.

Created on: 09.11.2016 at 18:07:51