01.07.2019 03:04

Tournament rating is calculated using ELO system using the following formula (for two players А and В):

R_{а, new} = R_{а, previous} + К * (С_{а} - Е_{а})

R_{а, new} – new rating of player A in the tournament;

Р_{а, previous} – current rating of player A in the tournament;

К – index 30 if rating value is less than 2000, index 20 – when rating is from 2000 to 2400, index 10 if rating value is higher than 2400;

С_{а} – number of points scored de facto by Player A (1 point for win, 0,5 for a draw game and 0 for loss );

Е_{а} – expected score for Player A, calculated on the basis of Player's rating.

Е_{а} = 1 / (1 + 10 ^ ( (R_{B, previous} – Р_{а, previous}) / 400 ))

Match result will influence the Players' global rating in the same way with the only difference – the Players' global rating will be used for calculation, not the tournament ratings.

$x=\frac{-b\pm \sqrt{{b}^{2}-4ac}}{2a}$