ChessPub Forum - Bishop Pair vs The Exchange

Keano God Member Offline Money doesn't talk, it swears. Posts: 2928 Location: Toulouse Joined: 05/25/05 Gender:	Re: Bishop Pair vs The Exchange Reply #18 - 07/15/16 at 10:13:48	Post Tools	Print Post
	A rule of Botvinnik which often is true is this: 1 Rook + 2 Bishops = 2 Rooks + 1 Knight


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iggystiv YaBB Newbies Offline I love ChessPublishing.com! Posts: 46 Location: Portland Joined: 03/22/03	Re: Bishop Pair vs The Exchange Reply #17 - 07/07/16 at 07:15:29	Post Tools	Print Post
	First of all; great topic.! What a rich subject to study and analyze. I just wanted to make a couple general observations for the human player (that I am). It doesn't seem to matter if it's an open board or not. The bishops can restrict the rook in a closed position and work all over the board in an open one. The bishop tandem just covers a lot of squares. It looks like the example showed that the bishops pushed their majority while holding back the rook. And then it came down to exchanging pawns when the superior side (rook and knight usually) tried to cash in . It always kinda seemed that simplification helped the defending bishops. Another thing that I noticed was that the knight was easily the worst piece on the board. I didn't see many great outposts for the knights in the examples. Lastly, I wanted to say that I appreciated all the examples and and analysis posted in all their various formats. Keep it coming in any which way shape or form.


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Stigma God Member Offline There is a crack in everything. Posts: 3277 Joined: 11/07/06 Gender:	Re: Bishop Pair vs The Exchange Reply #16 - 08/12/15 at 21:36:44	Post Tools	Print Post
	barnaby wrote on 08/12/15 at 18:30:23: Welcome to Chess in the modern age. It is only going to get more and more like this and the soon-to-be eventual future of the game is to just simply have engines stand in as proxies for the players (like they do now in "correspondance chess"). Chess isn't and never will be about how well computers can play. It's about how well humans can play, in direct combat under time pressure, even if to a larger and larger extent computers have played an essential part in their preparation. I've never understood why some people become so fascinated by computer chess, to the extent that it takes focus away from what really gives the game meaning: The human aspect and the psychology. How well can a machine successfully follow some random rules that have developed in the Indian, Persian, European etc. parts of the world over the centuries? Who cares?! Don't get me wrong, I love this game, but only when humans are involved. Even setting aside regular play, chess "sideshows" like problems and endgame studies depend largely on human aesthetic judgement.

	Improvement begins at the edge of your comfort zone. -Jonathan Rowson
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barnaby Senior Member Offline The night is dark and full of terrors. Posts: 345 Joined: 01/09/12 Gender:	Re: Bishop Pair vs The Exchange Reply #15 - 08/12/15 at 18:30:23	Post Tools	Print Post
	Smyslov_Fan wrote on 08/08/15 at 05:29:07: All this engine analysis leaves me cold. Welcome to Chess in the modern age. It is only going to get more and more like this and the soon-to-be eventual future of the game is to just simply have engines stand in as proxies for the players (like they do now in "correspondance chess"). The more one fights it, the more pain that person inflicts upon themselves. It was great fun while it lasted, mano a mano intellectual competition, but all things must pass.


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Smyslov_Fan God Member Correspondence fan Offline Progress depends on the unreasonable man. ~GBS Posts: 6902 Joined: 06/15/05	Re: Bishop Pair vs The Exchange Reply #14 - 08/08/15 at 21:25:22	Post Tools	Print Post
	Good point, Bibs. I don't mind some images such as graphs being used, but you are right. These are massive. I have left the most recent post in place to allow Nordlandia the opportunity to edit it himself, but I edited two others.


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Bibs God Member Offline Posts: 2343 Joined: 10/24/06	Re: Bishop Pair vs The Exchange Reply #13 - 08/08/15 at 13:14:18	Post Tools	Print Post
	Moderators - the massive pics are cluttering stuff up. can you delete please, and encourage a focus on a less 'decorative' approach? Cheers B


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Vass God Member Offline I Love ChessPublishing! Posts: 1105 Joined: 06/22/11	Re: Bishop Pair vs The Exchange Reply #12 - 08/08/15 at 07:23:02	Post Tools	Print Post
	Smyslov_Fan wrote on 08/08/15 at 05:29:07: All this engine analysis leaves me cold. ...And comfortably numb...


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Smyslov_Fan God Member Correspondence fan Offline Progress depends on the unreasonable man. ~GBS Posts: 6902 Joined: 06/15/05	Re: Bishop Pair vs The Exchange Reply #11 - 08/08/15 at 05:29:07	Post Tools	Print Post
	All this engine analysis leaves me cold.


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Nordlandia

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Re: Bishop Pair vs The Exchange
Reply #10 - 08/07/15 at 09:29:45

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[quote="Director"]Obviously huge difference once i switch the CPU for playing the white pieces. [/quote]

Download game in pgn format

In-depth analyse - http://en.lichess.org/Ygx8RTlC#0

[quote="User"]Comparison between how the two CPU's handles the white pieces. [/quote]

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Nordlandia

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Re: Bishop Pair vs The Exchange
Reply #9 - 08/06/15 at 16:54:10

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Quote:

An unblanced position has arisen straight out of the opening, in which, with an open centre, Black has a pawn and the bishop pair for the exchange. Is it enough compensation?

Intel Pentium E5200 ⚔ i7-5960X Processor Extreme
90m + 90s

White
Cpu: Intel Pentium E5200 @2.50GHz (2 CPU)
Gui: Arena 3.5
Hashtable: 2048 Mbytes
Tablebases: Syzygy 5-men
Permanent Brain: On
Os: Windows 10 Preview

Black
Cpu: i7-5960x Extreme Edition @3.90GHz (16 CPU)
Gui: Arena 3.5
Hashtable: 4096 Mbytes
Table Memory Komodo: 256 MB
Comtempt Factor Komodo: -10 (default -10)
Tablebases: Syzygy 5-men
Permanent Brain: On
Os: Windows 10 Build 10240

Download game in pgn format

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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #8 - 08/04/15 at 14:22:57	Post Tools	Print Post
	«A pair of bishops shouldn't be underestimated, but the rook and knight are still superior» Quote: Glen Flear: The defender probably has more chances of successfully defending with the pair of bishops than "with other minor piece combinations. This seems to hold true even when the board isn’t opened up for bishops. Indeed, there is a certain school of thought that claims that ’a pair of bishops equals a rook and knight in the ending’. I’m not sure that this assertion can be proven, but I decided to look at it from a statistical point of view. From a sample of 68 high-level games in the NQE of rook and knight vs two bishops (this time with players rated 2550 and above), there were 30 wins for the rook and knight duo, 20 for the bishop pair, and 18 draws. The number of wins achieved by the bishops seems quite high, which may reflect the double-edged nature of this imbalance, but the overall percentage is a respectable 57% to 43%. We can interpret this as such: a pair of bishops shouldn't be underestimated, but the rook and knight are still superior. Quote: Indeed, two bishops and a pawn are often sufficient compensation for a rook and knight, but here the decisive role is played by defects in the pawn structure. Although, of course, Black's tasks is not easy: in some cases the bishops together with the queen are able to spring an unpleasant suprise. - My Great Predecessors, Part II, Game 93 Download game in pgn format


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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #7 - 05/30/15 at 01:42:10	Post Tools	Print Post
	Quote: In open positions where the knight has no outposts in the centre, the strength of two bishops and a pawn is no less (and tends to be greater) than that of a rook and knight Download game in pgn format


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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #6 - 05/25/15 at 17:06:30	Post Tools	Print Post
	Quote: The bishop pair is also very capable of compensating for a material deficit; it is, e.g., well-known that in open positions the bishop pair combined with a rook is stronger than the combination of two rooks and a knight. This exiting game shows the power of the Bishop Pair and it's capability of compensating for a material deficit. Download game in pgn format


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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #5 - 05/25/15 at 07:48:33	Post Tools	Print Post
	≤ means less than or equal to. 2 Bishops + 1 Pawn ≤ R+N You're right the chances are on the RN side obviously. 40-60 chance \| 35-65? In the setup-game white scores much better if the pawn that is removed to offset black's exchange is one of the central pawns. Edited: Edited to remove a large image and replace it with text, in blue. ~SF August 8, 2015
	« Last Edit: 08/08/15 at 21:22:37 by Smyslov_Fan »

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Girkassa Senior Member Offline I Love ChessPublishing! Posts: 433 Joined: 04/07/07	Re: Bishop Pair vs The Exchange Reply #4 - 05/24/15 at 20:28:01	Post Tools	Print Post
	I don't think it is "enough" as in "equal chances" - in both the actual game and the constructed computer game, it is clear that the winning chances are with the r+n player. I am not surprised that Flear managed to draw, though. His active bishops had time to provoke a weakness on g3 before White could activate his pieces. In contrast, the bishops didn't have any initial development advantage in the computer game.


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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #3 - 05/24/15 at 06:42:25	Post Tools	Print Post
	Quote: «Claimed that two bishops versus rook and knight were equivalent. I don’t believe that this is the case, i.e., I think the extra material will usually win out, but this view continues to influence chess thinking to some extent even today» - Steve Mayer 1997 In this case Steve Mayer was right the extra material won in the long run. White has the bishop pair + pawn for the exchange - can white hold with optimal play here? The h7 pawn is worth less than the remaining pawns so it isn't quite worth a full pawn. Emanuel Lasker valued the rook pawn to be worth 0.5 points. Bishop Pair = 0.5 + 0.5 = 1.00 + 6 = 7 In this experimental position, black have 1 pawns advantage. Is it enough to win? Download game in pgn format


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bearheart YaBB Newbies Offline I love ChessPublishing.com! Posts: 23 Location: Mound Joined: 02/19/05	Re: Bishop Pair vs The Exchange Reply #2 - 05/23/15 at 20:50:14	Post Tools	Print Post
	If it were White's move then I would say White wins; however, Black takes the Knight and with the center open along with those sweeping Bishops, I believe that it is a draw. Anyone own an endgame database that can check it out, or perhaps someone could persuade Karsten Mueller to comment? Just a patzer, here...


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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Re: Bishop Pair vs The Exchange Reply #1 - 05/23/15 at 14:07:27	Post Tools	Print Post
	Quote: «Many of the Classicists of the late nineteenth and early twentieth century claimed that two bishops versus rook and knight were equivalent. I don’t believe that this is the case, i.e., I think the extra material will usually win out, but this view continues to influence chess thinking to some extent even today» - Steve Mayer 1997 Quote: «When the side down the Exchange has the bishop pair, my data shows he needs only 1.15 pawns to make things even» - Larry Kaufman Edited: Post edited to remove a large image ~SF August 8, 2015
	« Last Edit: 08/08/15 at 21:18:28 by Smyslov_Fan »

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Nordlandia YaBB Newbies Offline I Love ChessPublishing! Posts: 16 Joined: 05/23/15	Bishop Pair vs The Exchange 05/23/15 at 05:44:54	Post Tools	Print Post
	Download game in pgn format An unbalances position has arisen straight out of the opening, in which with an open centre, Black has a pawn and the bishop pair for the exchange. Is it enough compensation?


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