Chess tournaments are played according to different tournament systems. However, almost in every system happens, that some of the players have the same amount of points at the end of the tournament. In the past, the players were placed on shared places or they played an additional game to decide their ranking. A majority of chess tournaments played today have some additional criteria to decide the final ranking of players. Tie breaks are not unified – there is a whole range of them and every single tournament has clearly stated what happens if there is an equality of points among players. The most common system is that one criterion is used to evaluate the players. If the value is the same for both players, the another criterion is used, etc. Sometimes, an additional game between players is required to determine the final ranking.
The most used tie break criteria
In the following article, we will try to describe the two of the most used criterion systems: The Sonneborn – Berger system and the Buchholz system.
Sonneborn – Berger system (or SB system)
This system prefers players, that were more successful in games against stronger opponents. It is used only in tournaments where player has to play with every other player in the tournament. A player gains the total amount of tournament points of the player he had defeated. For every tied game, the player gains half of the tournament points of his opponent.
It is interesting that this system was not established by gentlemen Sonneborn and Berger – in a fact, they were loudly protesting against this system. The system was invented by Hermann Neustadtl in 1882 which is why it is called more properly “Neustadtls score” in Britain.
According to this system, the tie break is counted by the total amount of points that the player´s opponents won. This system can only be used when a player does not play with every other player. It is mainly used for Swiss-system tournaments and for the first time it was used in 1932 on the tournament in Bitterfeld.
Even this system has its opponents and later, some other systems were established on its basis. For example, the Median – Buchholz system which does not count the player with highest and lowest points.
Other decisive criteria
There is a whole lot of criteria that helps to decide player´s ranking. Currently, there is about several tens of various systems and criteria. Some of them prefers players that do not draw often (Kashdan system), others count the average rating of opponents (ARO or AROC) and in another the mutual game counts.
Outside tournaments, for example in the world championship match there are different tiebreaks in the case of draw – additional shortened chess games such as this year´s match between Magnus Carlsen and Sergei Karajakin.