Chess rating system

A chess rating system is a system used in chess to estimate the strength of a player, based on his performance against other players. They are used by all national chess organisations, and by FIDE, the International Chess Federation. In these systems a higher number indicates a stronger player. In general, a player's rating goes up if he performs better than expected and down if he performs worse than expected. The Elo rating system is used by FIDE and by many countries.

The first modern rating system was used by the Correspondence Chess League of America in 1939. Soviet player Andrey Khachatoruv proposed a similar system in 1946. The first one that made an impact on international chess was the Ingo system in 1948. The USCF (United States Chess Federation) adopted the Harkness system in 1950. Shortly after, the British Chess Federation started using a system devised by Sir Richard Clarke, a statistician and senior civil servant. The USCF switched to the Elo rating system in 1960, which was adopted by FIDE in 1970.Hooper, David & Whyld, Kenneth 1992. The Oxford Companion to Chess. 2nd ed, Oxford University Press. p332 

 The underlying principle 
The principle which lies behind a rating is this. The rating is a prediction of how well a player will perform against other players of different ratings. If the player does better than predicted, their rating goes up; if they do worse, their rating goes down. An arithmetic calculation shows by how much the player's rating changes. Today, all results are fed into a computer database, and computer software does all the calculations. Then the list is published as a 'rating list'.

History
1933 – The Correspondence Chess League of America (now ICCF U.S.A.) is the first national organization to use a numerical rating system. 
1942 – Chess Review uses the Harkness system, an improvement of the ICCF system.Harkness, Kenneth 1967. The official chess handbook. McKay
1946 – The USSR Chess Federation uses a non-numerical system to classify players. This is a national system of master titles.
1948 – The Ingo system is published and used by the West German Chess Federation.
1950 – The USCF starts using the Harkness system and publishes its first rating list in the November issue of Chess Life.  Reuben Fine is first with a rating of 2817 and Sammy Reshevsky is second with 2770.
1959 – The USCF names Arpad Elo the head of a committee to examine all rating systems and make recommendations.
1961 – Elo develops his system and it is used by the USCF. It is published in the June 1961 issue of Chess Life 
1970 – FIDE starts using the Elo system. Bobby Fischer is at the top of the list.
1978 – Elo's book (The rating of chessplayers, past and present) on his rating system is published.
2001 – the Glicko rating system is published.
2005 – Chessmetrics is published by Jeff Sonas.

 References 

Category:Chess