31
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Why does chess.com consider this promotion a blunder?
50 points sounds huge, but there actually is no meaningful difference between -6.4 and -62 in such an endgame.*
6.4 is more or less "Black has a queen for a bishop (but I haven't found a way to ...
- 5,888
28
votes
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Stockfish blunders away a piece
This is not a blunder, expected behaviour from the engine. Everything worked as intended. Try to copy the FEN string out, and you'll know.
Although the position looked winning, White didn't have ...
- 22.3k
24
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Is this really played by 2200+ players?
In short, after some investigation, I do not believe that white was a 2200 player is the real answer. First, I found it odd that it says he was exactly 2200. This is the only tournament I can find ...
- 32.4k
24
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Why is g3 a bad move here?
Pawn structure.
Allowing the exchange ...Nxf4 gxf4 simply weakens your structure considerably. The pawns on f2, f4 and h2 are disjointed and cannot protect each other anymore.
Black can immediately ...
- 5,888
23
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Why does chess.com consider this promotion a blunder?
This sounds like a bug. Using Lichess's analysis engine, it takes Stockfish 14 less than ten seconds to find a mate in 11 moves. Both 1...Kg3 and 1...g1=Q lead to mate in 11.
So there should be no ...
- 24.9k
21
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Improving the observation skill & making less blunders
I will go back to what Artur Yusupov, three-time World Championship Candidate, former top-10 player, and one of the greatest living trainers recommends in the first book of his 10-volume series. In ...
- 32.4k
21
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Has there been any blunders in resignation?
The official source that people link to when this question comes up is Tim Krabbe's excellent blog post from more than 20 years ago now: The ultimate blunder. He collected every single game in the ...
- 15.1k
17
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Is this really played by 2200+ players?
White (Rigaud) did not have a Fide rating.
Until 1981, the Fide rating floor was 2200, which means that any rated player had at least 2205 and that non-rated players taking part in a Fide-rated ...
- 14.7k
17
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Why is Qf5-c2+ a blunder?
The engine considers Qc2+ a blunder because it's a draw by repetition. (I think the position is probably a draw anyway, but Black could at least try for a win.) The problem is that you have already ...
- 1,293
15
votes
Opening positions where declining a gambit is a blunder
Sure, for example the Halloween Gambit. This is not a sound gambit at top levels of play, but if White plays it, Black must accept. The alternatives are even worse.
[FEN ""]
1. e4 e5 2. Nf3 ...
- 24.9k
13
votes
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Probability of making a game-losing move as a function of Elo?
Coincidentally I already answered exactly this question in response to a similar question.
Edit: This similar question was about frequencies of blunders in games, which made the analysis somewhat ...
- 19.1k
13
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Why is g3 a bad move here?
Other answers have made many good points. But the main reason g3 is a bad move can be reduced to a very simple explanation: The knight on h5 is a very bad piece, it has almost no squares to go to and ...
- 485
13
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Why did Lichess annotate this as a blunder?
Its evaluation drops form +2.3 to +0.0, so it considers it a blunder. Of course this does not match what a human understands as "blunder", but computers are incapable of identifying that.
...
- 16.1k
12
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What is the difference between an inaccuracy, a mistake and a blunder on lichess?
Blunder: 300 centipawns
Mistake: 100 centipawns
Inaccuracy: 50 centipawns
This is sourced from http://en.lichess.org/qa/75/how-are-these-determined-blunder-mistake-and-inaccuracy
It is the first ...
- 788
12
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What are the worst blunders ever committed in a world championship match (final)?
By far, the biggest blunder in all world championship is absolutely 32.Bb4?? played by Chigorin in the 1892 match. He threw away the win and the match, landed himself to mate in 2.
https://en....
- 22.3k
11
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Can computer analysis really understand human behavior?
This response will be very critical of OP's attitude to chess analysis, and I realize that it may even come across as somewhat harsh. However, it is assumed below that OP is interested in improving, ...
- 7,948
11
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I am trying to understand chess moves
14.Nxd4 takes a pawn on d4, and it attacks the bishop on h5. So if black takes back with 14...cxd4, then white has 15.Bxh5, leaving white a pawn up (knights and bishops have roughly the same value). ...
- 27.5k
10
votes
Improving the observation skill & making less blunders
One of the most important things we tell players who are a bit above beginner level is to have a checklist they go through before making each move. It looks like this:
checks
captures
threats
...
- 89.7k
10
votes
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How do Stockfish levels work?
Since I could not find any complete explanation, I followed the eternal advice "Use the source, Luke". The Stockfish authors did a great job because their code is easily followable and ...
- 3,336
10
votes
Opening positions where declining a gambit is a blunder
Some gambits whose best response is to accept.
1 e4 c5 2 d4 cxd4 4 c3: Sicilian Defence, Smith-Morra Gambit
1 d4 Nf6 2 c4 e5 3 dxe5 Ng4 4 Bf4 Nc6 5 Nf3 Bb4+ 6 Nbd2 Qe7: Budapest Gambit
1 e4 e5 2 Nf3 ...
- 6,207
9
votes
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What percent of chess games contain a blunder?
I happen to have a dataset with 25000 games with stockfish evaluations after every move. I just did a little blunder search and these are my findings:
Blunders from an equal position (-1.00 < ...
- 19.1k
9
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Has a "resignation blunder" ever been refused?
Some quick Googling suggests that the rules (or at least some sets of rules) do allow you to refuse a resignation from your opponent
This does not reflect the FIDE Laws of Chess. According to Article ...
- 89.7k
8
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Having knightmares, what to do?
The solution is: play better chess. Train your tactical skills so you can better anticipate the opponent's knight's threats (and also make a better use of your own knights). Avoid creating weak ...
- 16.1k
8
votes
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Why did Lichess annotate this as a blunder?
The "blunder" annotation is derived from server-side analysis using a low engine depth, which is usually inaccurate.
- 96
8
votes
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Why is Bxf2+ a blunder in the Traxler Counterattack,?
After 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5, now 4....Bc5 is a mistake by Black. If White goes 5. Nxf7 then following up with 5...Bxf2+ is the best move in that position, so definitely far from a blunder. ...
- 16.1k
7
votes
How can I STOP hanging pieces?
You speak the language of my people.
There's nothing magical, unfortunately. You must avoid 'target fixation'. That is, even if you're close to delivering mate, you have to stop before every move, ...
- 20.1k
7
votes
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Frequency of resigning in won positions
There is a comprehensive list on Tim Krabbé's page The Ultimate Blunder.
- 14.8k
7
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What I thought was winning tactic, apparently was mistake
First of all, I don't think it is productive to call moves "blunders" when they're just not the best moves according to the computer. Chess is a game between humans. I like to reserve "blunder" for ...
- 14.8k
7
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What are the worst blunders ever committed in a world championship match (final)?
Game six in the second Carlsen-Anand match comes to mind.
After 26.Kd2 black can simply take on e5 and after 26...Nxe5 27.Rxg8 he has the intermediate check 27...Nxc4+. Black just remains at least ...
- 19.1k
7
votes
What are the worst blunders ever committed in a world championship match (final)?
As it happens Chessbase ran a story earlier this week featuring
"eight egregious elite errors"
from past World Championship matches. They are Chigorin-Steinitz (noted by SmallChess), Bronstein-...
- 6,454
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