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Elo Formula

The rankings on this page are calculated with the Elo formula.
The Elo system is based on probabilities, each club has an Elo value based on its past performance. The difference between two clubs' Elo values represent the probability of one team winning against the other team. This probability can also be called result expectancy. Results and result expectancies can be expressed as percentages or fractions of 1. A victory is 1 (100%), a draw is 0.5 (50%) and a defeat is 0 (0%).
If two teams play each other, the result expectancy can be calculated according to the Elo formula:
E = 1 / (10(-dr/400) + 1),
where dr is the Elo point difference of the 2 clubs.

Result Expectancy90%80%70%60%50%40%30%20%10%Elo Points Difference-400-2000+200+400

The result expectancy will be somewhere between 1 and 0. A team winning will always exceed the result expectancy and steal points from the losing team. The number of points stolen is determined by the following formula:
P = W * F * (R-E),
where R is the actual result and E is the result expectancy, W is a weight index and F is an additional factor depending on the margin of victory. High victories can be seen as more significant, so the number of stolen points increases.
The Elo system is a zero-sum game, points that are won by one team are lost by its opponent and vice versa. If a team exceeds expectations, it wins Elo points, if it stays behind expectations, it loses Elo points.

Created: 23 Mar 2013 - Modified: 20 May 2012