For more information about the Rating System we operate see the Rating System FAQ.
Many BGA tournaments are run on the McMahon system, which tries to pair players of equal strength. This relies on players entering the tournament at a realistic grade so that fair games between players can be achieved. Many European tournaments are also run on the McMahon system, so again we would like to ensure that our players perform satisfactorily in European events. Consequently the aim of the BGA ratings policy is:
It is recognised that not all players are able to play in every tournament and some players' published ratings may lag excessively behind their actual playing strength. To address this issue, the BGA policy regarding which games count towards rating points is as follows:
The policy is:
The BGA encourages on-line players to enter over-the-board tournaments. In order to establish a relation between on-line server grades and BGA strengths we will be setting up a system to collect information from players who play in tournaments as well as on-line. Until a meaningful correlation between server and BGA grades is established, the following guide will apply for an on-line player entering a BGA tournament for the very first time or after a long absence:
The BGA monitors the progress of BGA members' ratings and awards official dan certificates when specified targets have been reached. Official dan certificates are never revoked, even if a player's rating subsequently falls.
BGA dan certificates since November 2003 have been awarded based on the BGA ratings, which are in turn based on the European ratings. You will be awarded an X dan certificate when:
In addition:
Players with official dan certificates are entitled to enter tournaments at that grade, but are encouraged to enter them at a grade equal to the strength listed on the current version of the BGA ratings page, rounded to the nearest whole number. Anyone wanting to enter tournaments outside the range from their official certificate grade to their rounded strength should seek approval from the BGA Council before doing so.
We respect grades assigned by foreign Go organisations to those resident abroad.
In the first instance tournament directors are encouraged to be proactive in ensuring that their players are entering at realistic grades. The results of all BGA tournament are scrutinised and submitted to the EGF by the BGA ratings official. If anomalous entry grades are present in the results, submission of games to the EGF rating system may be delayed and the following procedure adopted:
It is very much hoped that players' entry grades are essentially self managed, and much information is provided to help players determine their entry grades. However, if any player wishes to complain about the published rating of either themselves or another player on the BGA rating list then the following procedure must be adopted:
In order to accommodate the varied ratings strategies in Europe, the BGA calibrates our strengths against the whole of the European database of players. This is achieved by means of a least squares fit (linear regression) of player's ratings versus grade. As at April 2010 this leads to the formula
strength=(rating−2038)/95.1
This means that a nominal shodan (rating 2100) has a strength of 1.7d rather than 1.0d. It is for this reason
that rating resets in the dan grades have to be very carefully controlled.
The BGA will continue to monitor the rating/grades relationship to identify any action on our calibration procedure that may be required in the future.