When Chess Players Blunder

An anonymous reader writes: Joe Doliner has done a statistical analysis of mistakes in rated chess games. He used a chess engine called Crafty, which is capable of not only finding mistakes, but quantifying how bad they are. After crunching all the matches on chessgames.com in 2014, which amounted to almost 5 million moves, Crafry found only 67,175 blunders that were equivalent to a 2-pawn deficit or worse. With a pair of graphs, Doliner shows how mistakes decrease as player rating increases, as you'd expect. According to the trendline, gaining 600 rating points roughly halves the number of mistakes a player makes. He made the data and tools available in a public repository for others to dig into.

Comments

Cause meet Effect.

[thesupraman]

I would suggest that making half as many mistakes gains you about 600 rating points, rather than the other way around.
Unless those points can be magically sprinkled on a player in some form..
But hey, cause and effect seem to be highly, shall we say, flexible these days.

(yes, I know its all semantics here, but hey..)

Re:Cause meet Effect.

[Paradise Pete]

I would suggest that making half as many mistakes gains you about 600 rating points

I think the big problem is that a "mistake" is being defined so crudely. I'll bet players make about the same number of mistakes no matter how good they are, but what they actually qualify as a mistake gets smaller and smaller.
It's certainly true for me. I play at about a 1900 level now and was 2200 in my youth. I make tons of mistakes, but at the same time hardly a week goes by when somebody doesn't accuse me of using a computer. In other words, they don't see the mistakes. But I know they're there and to players better than I they are obvious mistakes. But almost none of them are "2 pawn +" blunders.

Blunder of the Century

[DNS-and-BIND]

Deep Fritz 10 - Kramnik,V (2750). Man vs Machine Bonn, Germany, 27.11.2006. Kramnik played 34...Qe3?? The blunder of the century.

Kramnik played the move 34...Qe3 calmly, stood up, picked up his cup and was about to leave the stage to go to his rest room. At least one audio commentator also noticed nothing, while Fritz operator Mathias Feist kept glancing from the board to the screen and back, hardly able to believe that he had input the correct move. Fritz was displaying mate in one, and when Mathias executed it on the board Kramnik briefly grasped his forehead, took a seat to sign the score sheet and left for the press conference, which he dutifully attended.

In the post match press conference Vladimir Kramnik confirmed that he had not blundered out of exhaustion, and had been calculating very well right to the end. He had no real explanation for the oversight that happened right at the end.

Kramnik in the press conference: "It was actually not only about the last move. I was calculating this line very long in advance, and then recalculating. It was very strange, some kind of blackout. I was feeling well, I was playing well, I think I was pretty much better. I calculated the line many, many times, rechecking myself. I already calculated this line when I played 29...Qa7, and after each move I was recalculating, again, and again, and finally I blundered mate in one. Actually it was the first time that it happened to me, and I cannot really find any explanation. I was not feeling tired, I think I was calculating well during the whole game... It's just very strange, I cannot explain it."

Thus the question that everyone was asking remained unanswered: how can a player of Kramnik's caliber, a world champion who hovers around the Elo 2800 mark, overlook a mate in one move? Naturally there is no logical explanation â" we have to delve into the realm of pattern recognition and the psychology of human perception if we want to understand anything.

The rest of the article turns the board around, looks at it from Kramnik's position, and tries to get into his head to see what he was thinking. Personally, I think it's what I call "sniffing your own butt" when you get so inside yourself, you stop thinking about the rest of the world. You then perform bizarre actions which seem quite reasonable to you. This happens in groups as well. It helps to explain things like how pro-worker governments of the 20th century murdered millions of workers. There's just nobody there to second-guess your thinking, and even if there was, they would be heavily punished for speaking out and contradicting you. This is where crowdsourcing shines.

Unfortunately, Kramnik had somehow not registered the threat generated by the Fritz move 34.Nxf8. The white queen threatens mate in one on h7 (where it is protected by the knight). Black does nothing to neutralise this threat with his move 34...Qe3. And so, after he played it, Kramnik was immediately mated by the computer.

But how could he not have seen the threat after 34.Nxf8. An explanation was proffered by a very experienced chess player and trainer, Alexander Roshal, who is also the editor of the Russian chess magazine "64".

Alexander told us that the mating pattern that occurred during the game, with the white queen protected by a knight on f8 (as in the screen shot above), is extremely rare in chess. It is not one of the patterns that chess grandmasters automatically have in their repertoire. This was confirmed by a GM commentator in Bonn, who after Kramnik's move did not notice that it was a blunder and started discussing White's options â" but not the mate in one.