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Tuesday, June 25, 2013

Modern Ratings

      According to an interesting Chessbase article dated Feb. 24, 2012 an oddity in the FIDE rating system allows some players to gain rating points quite easily. As I understand it, part of the problem has been a result of the FIDE giving everybody who participates in an FIDE rated event a rating. For example, if you are rated at least 1400 Elo, FIDE declares you have an 8% chance against the world number one.
      The article was a discussion by Jeff Sonas, statistician and creator of Chessmetrics, Ken Thompson, chess computer pioneer and GM John Nunn, mathematician.
      One example cited was the case of Chinese GM Li Chao whose rating went over 2700 after gaining 5.6 Elo points as a result of scoring 9 out of 9 at the 5th Colombo International Chess Festival 2012. Li Chao’s performance rating was actually 71 points below his then current rating and 6 of the eight rated opponents had ratings under 2000; one was even rated 1405.
      Jeff Sonas stated it was his understanding is that this rule was introduced for political reasons purportedly to give top players some incentive to play in open events. Sonas pointed out if someone strong were to play in lots of events with low-rated opponents and the rating administrators looked the other way, a strong player would likely be able to boost their own rating a bit. Does that sound a lot like Claude F. Bloodgood’s manipulation of the USCF rating system of years gone by?
      Ken Thompson felt that while it was possible, he observed “a player would have to spend lots of silly time pounding on weak players to gain points. He has to continually keep vigilance to accomplish this. One mistake and he will lose many times what he has slowly gained.” Well, that’s exactly what Bloodgood did. Also, Many years ago when masters were few and far between there was a local expert who, try as he might, could never break 2200; he got to 2199 a couple of times, but then would fall back to 2100-plus. His solution? He became a TD and held rinky-dink events nobody but under 1500’s or so played in. He would always manage to play a game as a “house man” which he always won and thus picked up a point or two. Eventually his rating hit a solid 2202 and he “retired” and advertised himself as a master.
      John Nunn advised, “ this rule was introduced to prevent players losing Elo points by winning a game. If one player in a tournament is rated far below the others, then including that player can lower the average rating of your opponents by so much that your expected score is increased by more than one point. Then beating that player will leave you worse off than if you had not played him at all. This is not just an academic situation. For very strong players it could easily happen in cases where, for example, a strong tournament includes a 'local player' who is much weaker than the others, or in Olympiads where your first round opponent was relatively weak.” As Nunn pointed out, boosting one’s rating like this could be very time consuming.
      In a related article dated back in 2009, Chessbase discussed rating inflation: ".A general improvement of chess skills? A larger number of players in the rating pool? The way the initial ratings are conducted? In this clearly written article statistician Jeff Sonas addresses these questions. Read Article
      A recent Chess Vibes articles asks the question, “Was Fischer’s 1972 rating more significant than Carlsen’s present rating?” Kasparov thinks the answer is yes. Read Article

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