Capablanca's Theorem Q+N > Q+B

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Nordlandia
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Capablanca's Theorem Q+N > Q+B

Post by Nordlandia » Wed Sep 06, 2017 2:38 pm

It's common knowledge that rook + bishop work better than rook + knight. Likewise the queen + knight tend to work better than queen + bishop in the endgame because the queen + bishop duo can sometimes be redundant.

The knight is unique compared to the bishop.
‘A bishop and a rook are also stronger than a knight and a rook, but a queen and a knight may be stronger than a queen and a bishop.’
Even when it's proven some people don't agree for some reasons.
‘... I don’t necessarily agree with the clichéd adage that “the queen and knight duo are superior”.
Statistically QN vs QB scores 55-57% on average against QB. That percentage is found by chessbase statistics.

What is your say?

http://www.chesshistory.com/winter/winter50.html

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hgm
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Re: Capablanca's Theorem Q+N > Q+B

Post by hgm » Wed Sep 06, 2017 3:13 pm

Queen could devaluate more against a Knight than against a Bishop, because it can be attacked by a Knight with impunity.

It would be interesting to see whether Q+N or Q+B perform better against a Chancellor + minor. Or whether C+B or C+N perform better against Queen.

Arpad Rusz
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Re: Capablanca's Theorem Q+N > Q+B

Post by Arpad Rusz » Wed Sep 06, 2017 3:34 pm

Nordlandia wrote:Likewise the queen + knight tend to work better than queen + bishop in the endgame because the queen + bishop duo can sometimes be redundant.
This might be true but it doesn't hold against two rooks: QN vs RR is a general draw while QB vs RR is a general win. The rook pair's main resource is the third rank defence which can be broken only by the Q+B duo. The key to success seems to be the bishop's ability to attack the first rank. An example:

[D]8/8/8/8/6kb/R4R2/3q4/5K2 b - -

The shortest win is 1...Bf2! -+

MikeGL
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Re: Capablanca's Theorem Q+N > Q+B

Post by MikeGL » Wed Sep 06, 2017 5:55 pm

Nordlandia wrote:It's common knowledge that rook + bishop work better than rook + knight. Likewise the queen + knight tend to work better than queen + bishop in the endgame because the queen + bishop duo can sometimes be redundant.

The knight is unique compared to the bishop.
‘A bishop and a rook are also stronger than a knight and a rook, but a queen and a knight may be stronger than a queen and a bishop.’
Even when it's proven some people don't agree for some reasons.
‘... I don’t necessarily agree with the clichéd adage that “the queen and knight duo are superior”.
Statistically QN vs QB scores 55-57% on average against QB. That percentage is found by chessbase statistics.

What is your say?

http://www.chesshistory.com/winter/winter50.html
Many chess authors agrees that Q+N is stronger in tandem versus Q+B, as long as
Q+N cooperate harmoniously. Best game I can remember is the young GM Kamsky against Kasparov. My memory didn't serve me right, just a draw. Kasparov halved the point with Q+N vs Q+R of Kamsky.


.

MikeGL
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Re: Capablanca's Theorem Q+N > Q+B

Post by MikeGL » Wed Sep 06, 2017 6:09 pm

Kasparov saving a lost game with his Q+N, forcing a draw.
Lucky escape by the legendary Kasparov

[pgn]
[Event "Interpolis 15th"]
[Site "Tilburg NED"]
[Date "1991.10.20"]
[EventDate "?"]
[Round "3"]
[Result "1/2-1/2"]
[White "Gata Kamsky"]
[Black "Garry Kasparov"]
[ECO "B84"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "90"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Be2 a6
7. a4 Nc6 8. Be3 Be7 9. O-O O-O 10. f4 Qc7 11. Kh1 Re8 12. Bf3
Rb8 13. Qd2 Bd7 14. Rad1 Na5 15. b3 Rec8 16. Nde2 Be8 17. Ba7
Ra8 18. Bd4 Nc6 19. Bxf6 Bxf6 20. Qxd6 Qb6 21. e5 Be7 22. Qd2
Bb4 23. Qd3 Rd8 24. Qe4 Qc5 25. Na2 Bd2 26. c3 a5 27. Nac1
Bxc1 28. Rxc1 Rac8 29. Ng3 Nb4 30. Rcd1 Qxc3 31. Qxb7 Qxb3
32. Rxd8 Rxd8 33. Qc7 Rd4 34. Ne4 Qd3 35. Rg1 Rxe4 36. Qc8 Kf8
37. Qc5+ Kg8 38. Qe7 g6 39. Qxe8+ Kg7 40. Bxe4 Qxe4 41. Rf1
Nd3 42. Qb5 Qe3 43. h3 Nf2+ 44. Kh2 Qxf4+ 45. Kg1 Nxh3+
1/2-1/2
[/pgn]

.

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Nordlandia
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Re: Capablanca's Theorem Q+N > Q+B

Post by Nordlandia » Wed Sep 06, 2017 7:07 pm


Many chess authors agrees that Q+N is stronger in tandem versus Q+B, as long as
Q+N cooperate harmoniously. Best game I can remember is the young GM Kamsky against Kasparov. My memory didn't serve me right, just a draw. Kasparov halved the point with Q+N vs Q+R of Kamsky..
Chess authors tend to glorify Q+N positions and doesn't pay much attention to when Q+B is stronger. I think the idea behind this phenomena is to make readers aware of the mentioned quips.

Like i previously said. The theorem is statistically proven right. Nevertheless if you find yourself in QN vs QB endgame, QN duo advantage is comparable to home-field advantage in football.

lkaufman
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Re: Capablanca's Theorem Q+N > Q+B

Post by lkaufman » Wed Sep 06, 2017 10:50 pm

Nordlandia wrote:It's common knowledge that rook + bishop work better than rook + knight. Likewise the queen + knight tend to work better than queen + bishop in the endgame because the queen + bishop duo can sometimes be redundant.

The knight is unique compared to the bishop.
‘A bishop and a rook are also stronger than a knight and a rook, but a queen and a knight may be stronger than a queen and a bishop.’
Even when it's proven some people don't agree for some reasons.
‘... I don’t necessarily agree with the clichéd adage that “the queen and knight duo are superior”.
Statistically QN vs QB scores 55-57% on average against QB. That percentage is found by chessbase statistics.

What is your say?

http://www.chesshistory.com/winter/winter50.html
Where does that 55-57% figure come from? I just checked it out for myself and found that the QB scores almost 51%. Of course, you have to check for both colors, since White comes out ahead overall with either side of this configuration. The exact results will depend on your database, your threshold rating, your requirement for "persistence" (I use 3 plies), and your requirements regarding other material (I required no other pieces to be on the board, but any number of pawns as long as they are equal). Perhaps your requirements were very different?

My opinion is that in general bishops are better than knights, but with just a queen to assist each this advantage is much reduced though not completely eliminated.
Komodo rules!

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Nordlandia
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Re: Capablanca's Theorem Q+N > Q+B

Post by Nordlandia » Thu Sep 07, 2017 4:32 am

lkaufman wrote:Where does that 55-57% figure come from?
Chessbase 14's Similar Endgames search.

Searching this position with symmetrical structure (colors is not ignored) from master class rated 2200 up to 2800s

[d]3qk1n1/pp3ppp/8/8/8/8/PP3PPP/3QKB2 w - - 0 0

Image

Image

Image

My question to Kaufman: Is Q+N tandem eligible for material bonus for Komodo?

Yes, in majority of cases the bishop is most of the times the best minor piece. Capablanca's Theorem is the exception when combined with the queen in endgame.

lkaufman
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Re: Capablanca's Theorem Q+N > Q+B

Post by lkaufman » Thu Sep 07, 2017 6:12 am

Nordlandia wrote:
lkaufman wrote:Where does that 55-57% figure come from?
Chessbase 14's Similar Endgames search.

Searching this position with symmetrical structure (colors is not ignored) from master class rated 2200 up to 2800s

[d]3qk1n1/pp3ppp/8/8/8/8/PP3PPP/3QKB2 w - - 0 0

Image

Image

Image

My question to Kaufman: Is Q+N tandem eligible for material bonus for Komodo?

Yes, in majority of cases the bishop is most of the times the best minor piece. Capablanca's Theorem is the exception when combined with the queen in endgame.
symmetrical pawn structure greatly favors knights over bishops, so your methodology tell us nothing about queen + minor combination. Yes, Komodo does have a queen with knight bonus, but it is very small.
Komodo rules!

Lyudmil Tsvetkov
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Re: Capablanca's Theorem Q+N > Q+B

Post by Lyudmil Tsvetkov » Thu Sep 07, 2017 6:13 am

Nordlandia wrote:It's common knowledge that rook + bishop work better than rook + knight. Likewise the queen + knight tend to work better than queen + bishop in the endgame because the queen + bishop duo can sometimes be redundant.

The knight is unique compared to the bishop.
‘A bishop and a rook are also stronger than a knight and a rook, but a queen and a knight may be stronger than a queen and a bishop.’
Even when it's proven some people don't agree for some reasons.
‘... I don’t necessarily agree with the clichéd adage that “the queen and knight duo are superior”.
Statistically QN vs QB scores 55-57% on average against QB. That percentage is found by chessbase statistics.

What is your say?

http://www.chesshistory.com/winter/winter50.html
till when are you going to quote chess grandmasters from 100 years ago?

there are very few pure setting QN vs QB games.

what you do in a setting QRN vs QRB?

who is to prefer there?

QN better than QB, but RB better than RN.

what about QN + pawns vs QR?

what about QB + pawns vs QR?

is Q+B always necessarily redundant and bad?

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