Testposition 60 - Bishop vs Knight

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Karlo Bala
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Re: Testposition 60 - Bishop vs Knight

Post by Karlo Bala » Sun Jan 06, 2013 12:30 am

bob wrote: Bishop and knight are not "near equal" in an endgame with pawns on both wings. Bishop is clearly superior there as it can reach squares in one move that take a knight 2-3 (or more) moves to reach. I have an evaluation term for this, where I think the idea came from Fine/Kmoch/et. al.
That is an exaggeration based on one particular position. Pawns on both wings means nothing. Take for example the position from the famous Saidy vs Fischer (1964) game. Semi open position, pawns on both wings, no blocked pawns. Position is probably slightly better for black but Fischer won that game easily (partly because he is the Fischer).

[D]6k1/1p1n1ppp/p7/3p4/3P4/P7/1P3PPP/2B3K1 w - - 0 1
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Karlo Balla Jr.

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Re: Testposition 60 - Bishop vs Knight

Post by tano-urayoan » Sun Jan 06, 2013 4:34 am

Karlo Bala wrote:
bob wrote: Bishop and knight are not "near equal" in an endgame with pawns on both wings. Bishop is clearly superior there as it can reach squares in one move that take a knight 2-3 (or more) moves to reach. I have an evaluation term for this, where I think the idea came from Fine/Kmoch/et. al.
That is an exaggeration based on one particular position. Pawns on both wings means nothing. Take for example the position from the famous Saidy vs Fischer (1964) game. Semi open position, pawns on both wings, no blocked pawns. Position is probably slightly better for black but Fischer won that game easily (partly because he is the Fischer).

[D]6k1/1p1n1ppp/p7/3p4/3P4/P7/1P3PPP/2B3K1 w - - 0 1
Your example is different because of the d4-d5 pawns cut the board in two. This is different as premise of pawns in both wings without central pawns present which is the context made by Dr. Hyatt.

peter
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Re: Testposition 60 - Bishop vs Knight

Post by peter » Sun Jan 06, 2013 7:11 am

peter wrote:
Kyodai wrote:I remember Karsten Mueller mentioned an early barrier in his article

"White can try to build a barrier against Black's king directly with 6.f3 Ba6+ 7.Ke3 Kc5 8.Nc2 Bf1 9.g3"

and continues

"Usually the attacking side tries to break such set ups by zugzwang or by
opening a second front or a road for the king. But here it seems that White's narrow front does hold: 9...Ba6 10.Nd4 Bb7 11.Kd3 Kb4 12.Kc2 Bd5 13.Kb2 g6 14.Kc2 a6 15.Kb2"

"Black is still far away from victory according to Averbakh in his famous
classic series on the endgame. I even think that he cannot win at all. Maybe a reader can find a way?"

And here we are................................... 8-)
Now for Karsten Müller, if he says it to be draw, I tend to believe him just for his name, but let's see.
:)
Well, well, even if I managed to win from Karsten Müller's 6.f3 with 6...f6 instead of 6...Ba6+ against Houdini, I'm in big doubt, if I really could win it against Karsten Müller. (Remember, he is always right.)
:)

1... Kf8 2. Kf1 Ke7 3. Ke2 Kd6 4. Kd3 Kd5 5. h4 Bc8 6. f3 f6 (6... Ba6+ 7. Ke3
Kc5 8. Nc2 Bf1 9. g3 Ba6 10. Nd4 Bb7 11. Kd3 Kb4 12. Kc2 Bd5 13. Kb2 g6 14. Kc2
a6 15. Kb2 {KM's line}) 7. g3 g5 8. Ke3 gxh4 9. gxh4 a6 10. Ne2 Kc5 11. Kd3
Bf5+ 12. Kc3 Kd5 13. Kd2 Ke5 14. Ke3 a5 15. Nd4 Bd7 16. Ne2 Be6 17. f4+ Kd6 18.
Nd4 Bf7 19. Kd2 Bg6 20. Ke3 h6 21. Ne2 Bc2 22. Nd4 Bb1 23. Kd2 Bg6 24. Ne2 Kd5
25. Ke3 Bc2 26. Nd4 Bb1 27. Ne2 Kc5 28. h5 Bh7 29. Kd2 Kd5 30. Kc3 Ke4 31. Nd4
Bg8 32. Nc6 Bf7 33. Nxa5 Kxf4 34. Kd2 Bxh5 35. b4 Bf3 0-1
It took about 20 moves to get White in such zugzwang, that the game got lost and there are so many white moves in between, that should be checked for better altnernatives, that such a single variant doesn't proof anything no more once again.
I'd say White's chances to build up a fortress or at least a blocked position are good and it's a matter of very much lines to see the one and the other one win or save draw.
I can't prove it neither the one nor the other way, sorry
:oops:
Peter.

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Kyodai
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Re: Testposition 60 - Bishop vs Knight

Post by Kyodai » Sun Jan 06, 2013 12:13 pm

Oh, thanks for your work Peter!

Actually I think you're on the right track when trying to open up this tin can!

I have carried this position with me to form some general guidelines like

1) Black doesn't have to go for an early Ba6+ - it looks good for the eye - but
the bishop is rather soon needed on other squares - with other missions.

2) It looks like white's problems grow when 1 pawn on the kingside is changed,
so that there are 2 vs 2 pawns. I showed one such variant and position with
black's g4 and after fxg4 Bxg4 which white couldn't hold -
now you show another another one within the same theme. Point is that
the position opens up a bit with more squares for the black bishop and the
black king. /position below/

Both these basic criteria is to be found in your last variation - aimed for
breaking up Carsten's barrier - early f6 instead of Ba6+ - early change of
pawns with gxh4 8-) - and then look for the zugzwang!

My first reaction in your variant was Black's f4 instead of trying to hold with Nd4,
but after Bd5 soon transposes to the main line.

Very interesting - I'll check this one out further.

(looks like white has problems covering both squares of entrance b4 and e4)

[D]8/8/5p1p/p1k5/5P1P/1P2K3/4N3/1b6 w - - 0 27

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Kyodai
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Re: Testposition 60 - Bishop vs Knight

Post by Kyodai » Sun Jan 06, 2013 12:40 pm

And this is the position when the Carsten's tin starts breaking - white
has no better (as it seems) than to open up a bit with f4+

[D]8/7p/5p2/p2bk3/3N3P/1P2KP2/8/8 w - - 0 17

peter
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Re: Testposition 60 - Bishop vs Knight

Post by peter » Sun Jan 06, 2013 4:30 pm

Kyodai wrote: My first reaction in your variant was Black's f4 instead of trying to hold with Nd4,
but after Bd5 soon transposes to the main line.
Pity, it doesn't really transpose necessarily, I fear:
[Event "Bishop Superiority"]
[Site "The Hague"]
[Date "1928.??.??"]
[Round "?"]
[White "Stoltz"]
[Black "Kashdan"]
[Result "?"]
[Annotator "Larsson"]
[SetUp "1"]
[FEN "6k1/p2b1ppp/8/8/3N4/1P5P/5PP1/6K1 b - - 0 1"]
[PlyCount "52"]
[EventDate "1928.??.??"]

1... Kf8 2. Kf1 Ke7 3. Ke2 Kd6 4. Kd3 Kd5 5. h4 Bc8 6. f3 f6 7. g3 g5 8. Ke3
gxh4 9. gxh4 a6 10. Ne2 Kc5 11. Kd3 Bf5+ 12. Kc3 Kd5 13. Kd2 Ke5 14. Ke3 a5 15.
Nd4 Bd7 16. Ne2 Be6 17. Nd4 (17. f4+ $6 Kd6 18. Nd4 Bf7 19. Kd2 Bg6 20. Ke3 h6
21. Ne2 Bc2 22. Nd4 Bb1 23. Kd2 Bg6 24. Ne2 Kd5 25. Ke3 Bc2 26. Nd4 Bb1 27. Ne2
Kc5 28. h5 Bh7 29. Kd2 Kd5 30. Kc3 Ke4 31. Nd4 Bg8 32. Nc6 Bf7 33. Nxa5 Kxf4
34. Kd2 Bxh5 35. b4 Bf3) 17... Bd5 18. f4+ Kd6 19. Kd2 Be4 20. Ne2 Bb1 (20...
h6 21. Nc3 Bf5 (21... Bf3 22. Ke3 Bc6 23. Ne4+ Ke6 24. Nd2 Kf5 25. Nc4 a4 26.
bxa4 Bxa4 27. Nd6+) 22. Nd1 Be6 23. Ne3 Bxb3 24. Nf5+ Kd5 25. Nxh6 Ke4 26. Ng4
f5 27. Nh6 Be6 28. Nxf5) 21. Ng3 Kd5 22. Nh5 Ke6 23. Ng3 Bg6 24. h5 Bf5 25. Kc3
h6 26. b4 axb4+ 27. Kxb4 0-0
17.f4+ might be a white mistake, I can't win after 17.Nd4 till now anymore, think I'll have to go back further again or give in.
:(
Peter.

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Kyodai
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Re: Testposition 60 - Bishop vs Knight

Post by Kyodai » Sun Jan 06, 2013 6:25 pm

peter wrote:
Kyodai wrote: My first reaction in your variant was Black's f4 instead of trying to hold with Nd4,
but after Bd5 soon transposes to the main line.
Pity, it doesn't really transpose necessarily, I fear:
[Event "Bishop Superiority"]
[Site "The Hague"]
[Date "1928.??.??"]
[Round "?"]
[White "Stoltz"]
[Black "Kashdan"]
[Result "?"]
[Annotator "Larsson"]
[SetUp "1"]
[FEN "6k1/p2b1ppp/8/8/3N4/1P5P/5PP1/6K1 b - - 0 1"]
[PlyCount "52"]
[EventDate "1928.??.??"]

1... Kf8 2. Kf1 Ke7 3. Ke2 Kd6 4. Kd3 Kd5 5. h4 Bc8 6. f3 f6 7. g3 g5 8. Ke3
gxh4 9. gxh4 a6 10. Ne2 Kc5 11. Kd3 Bf5+ 12. Kc3 Kd5 13. Kd2 Ke5 14. Ke3 a5 15.
Nd4 Bd7 16. Ne2 Be6 17. Nd4 (17. f4+ $6 Kd6 18. Nd4 Bf7 19. Kd2 Bg6 20. Ke3 h6
21. Ne2 Bc2 22. Nd4 Bb1 23. Kd2 Bg6 24. Ne2 Kd5 25. Ke3 Bc2 26. Nd4 Bb1 27. Ne2
Kc5 28. h5 Bh7 29. Kd2 Kd5 30. Kc3 Ke4 31. Nd4 Bg8 32. Nc6 Bf7 33. Nxa5 Kxf4
34. Kd2 Bxh5 35. b4 Bf3) 17... Bd5 18. f4+ Kd6 19. Kd2 Be4 20. Ne2 Bb1 (20...
h6 21. Nc3 Bf5 (21... Bf3 22. Ke3 Bc6 23. Ne4+ Ke6 24. Nd2 Kf5 25. Nc4 a4 26.
bxa4 Bxa4 27. Nd6+) 22. Nd1 Be6 23. Ne3 Bxb3 24. Nf5+ Kd5 25. Nxh6 Ke4 26. Ng4
f5 27. Nh6 Be6 28. Nxf5) 21. Ng3 Kd5 22. Nh5 Ke6 23. Ng3 Bg6 24. h5 Bf5 25. Kc3
h6 26. b4 axb4+ 27. Kxb4 0-0
17.f4+ might be a white mistake, I can't win after 17.Nd4 till now anymore, think I'll have to go back further again or give in.
:(
hmm... and then f4 follows the move after and should suddenly hold??
That's not logical - but who knows?

Moving back I notice that 5.-Bc8 doesn't look necessary at all. The bishop
has a very good position on d7 - until further missions...
So I suggest 5.-f6! and then try the Karsten Barrier... Well - a tempo ahead
couldn't be that bad. It's more about finding the exact setup for black..

Lyudmil Tsvetkov
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Re: Testposition 60 - Bishop vs Knight

Post by Lyudmil Tsvetkov » Mon Jan 07, 2013 11:48 am

Kyodai wrote:This is merely a discussion (and a celebrated game!) of B vs Kn in an ending with pawns on both flanks.
Such an ending is very difficult to hold for white

[D]6k1/p2b1ppp/8/8/3N4/1P5P/5PP1/6K1 b - - 0 1

[pgn][Event "Bishop Superiority"]
[Site "The Hague"]
[Date "1928.??.??"]
[Round "?"]
[White "Stoltz"]
[Black "Kashdan"]
[Result "0-1"]
[Annotator "Larsson"]
[SetUp "1"]
[FEN "6k1/p2b1ppp/8/8/3N4/1P5P/5PP1/6K1 b - - 0 1"]
[PlyCount "39"]
[EventDate "1928.??.??"]

{This position is from Stoltz-Kashdan 1928. A celebrated ending where the
existence of pawns on both wings on an open board emphasizes the bishop's
superiority over the knight.} 1... Kf8 2. Kf1 Ke7 3. Ke2 Kd6 4. Kd3 Kd5 5. h4
Bc8 {Black's bishop helps push the white king backwards, enhancing the scope
of his own king.} 6. Nf3 Ba6+ 7. Kc3 h6 8. Nd4 g6 9. Nc2 Ke4 10. Ne3 f5 11. Kd2
f4 12. Ng4 h5 13. Nf6+ Kf5 14. Nd7 Bc8 15. Nf8 g5 16. g3 gxh4 17. gxh4 Kg4 18.
Ng6 Bf5 19. Ne7 Be6 20. b4 Kxh4 {and the passed h-pawn carried the day.} 0-1[/pgn]
I think the displayed position is won for black, in case black plays a5 instead of Kf8. This will make impossible the construction of an area through which the black king can not pass, and the superiority of the bishop in an endgame with play on 2 sides would prove decisive, unless some minor tactical details save the day.
After Kf8, however, white can construct an area through which the black king can not pass by playing b4, transferring the knight to c3, playing f3 (or even better f4, if black does not play g5) and developing the king to e3. In this way the white pawn on b4 will be controlling the a5 and c5 squares, the knight the b5 and d5 squares, the white king on e3 the d4 and e4 squares, and the rest of the accessible squares will be taken up by blocked pawns. It is difficult to imagine a zugzwang, because white pieces are pretty mobile. Thus, after Kashdan's Kf8, there is nothing complicated in the position, it is a simple draw.
Kashdan, however, missed the win by not playing a5.

After 1...Kf8 2.b4, the position could be won for black in case a pair of pawns on the king side is removed, because it would be difficult to construct the above area.

This is just my tiny amount of cents glancing at the position without analyzing too much.

It seems that in endgames, the bishop is favoured by play on 2 sides, lower number of pawns, bigger distance in between the pawns, friendly and enemy pawns placed asymetrically, while the knight would be favoured by exactly the opposite considerations.

Lyudmil

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Kyodai
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Re: Testposition 60 - Bishop vs Knight

Post by Kyodai » Mon Jan 07, 2013 8:10 pm

Thanks for your contribution and analyse Lyudmil!

Right now I have limited time but will be back with this position in a couple of days.

Regarding 1-a5 - i was under the impression that white worsen his position by playing an early b4 - have a look at the previous analyse - black won all those variations.

Most problems we have with the Karsten Mueller Barrier - built up by keeping
the b-pawn on b3 - putting the Kingside pawns on f3-g3-h4 - the King
somewhere on the third rank - and the Knight on d4 (c2-e2).

Worked like a locked tin can which we eventually forced to open up by white
having to play f4 (zugzwang)
The first variation black won but just waiting one move for white with f4
and then using the Knight for tactics looked sufficient for a draw.

That's a summary where I ended up keeping the black bishop on d7 and
actually start with 1-f6 - the problem being to find the ultimate setup for
black.

But I will surely have a look att your ideas - thanks!

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Rebel
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Re: Testposition 60 - Bishop vs Knight

Post by Rebel » Tue Jan 08, 2013 12:04 am

bob wrote:
Houdini wrote:
Kyodai wrote:Well, actually I would go a couple of steps further with this position - i.e.
I would rather call it "a distinct or clear advantage" for black. The main
issue for the bishop's supremacy is of course pawns on both flanks.
I would be shocked if this game were forcibly won for Black, or even if were considered as a clear advantage for Black.
It would strongly violate the near-equality of Knight and Bishop in chess.

Robert
Bishop and knight are not "near equal" in an endgame with pawns on both wings. Bishop is clearly superior there as it can reach squares in one move that take a knight 2-3 (or more) moves to reach. I have an evaluation term for this, where I think the idea came from Fine/Kmoch/et. al.
Agree, but only if there are no center pawns. If I remember correctly that is the official rule. As such I use it with a small bonus of 1/4 pawn.

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