Test position

Date: 16 Aug 2007 12:34:45
From: M Winther
Subject: Test position

Is there any chess program that, in the following test position,
avoids closing the position in this or the next move? Closing the
position with c5-c4 is very bad because white replies b3-b4 and then
black has no counterplay on the queen's flank. Although white's bishop
is closed in at a1, black also has a weakness at a3. White has the
king's flank to himself.

No human player above 1300 in ELO would play c5-c4. It's a strategical
blunder of immense proportions. That's why this position is
interesting to use for testing positional understanding in a chess
engine. Fritz10, of course, plays c5-c4. But how about Hiarcs11, Rybka,
and other engines? Please test! You can either import the following as
PGN, or copy and paste the FEN code.

Mats
-------------------------------------

[Event "*"]
[Site "?"]
[Date "2007.08.16"]
[White "Test position"]
[Black "-"]
[Result "*"]
[SetUp "1"]
[FEN "r1r2nk1/1bq1bppp/1p2p2n/2ppP3/3P4/pPP2N1P/P2Q1PP1/BBR1RNK1 b - - 0 1"]
*

Date: 16 Aug 2007 16:36:45
From: David Kane
Subject: Re: Test position

"M Winther" <[email protected] > wrote in message news:optw5eb7x53bzrao@kalroten...
> Is there any chess program that, in the following test position,
> avoids closing the position in this or the next move? Closing the
> position with c5-c4 is very bad because white replies b3-b4 and then
> black has no counterplay on the queen's flank. Although white's bishop
> is closed in at a1, black also has a weakness at a3. White has the
> king's flank to himself.
>
> No human player above 1300 in ELO would play c5-c4.

This is certainly not true.1300's (and higher) make far more
straightforward blunders than this.

>It's a strategical
> blunder of immense proportions.

It would be educational for this player (somewhat >1300) to see actual analysis
supporting the "White has the king's flank to himself" claim. Or an example of
the "counterplay" when the Queenside isn't blocked.

Computers aren't trying to mimic human preference, but to win. Do you
beat these engines with Black before c4, or with White after c4 and b4?
If so, it would be interesting to post your games.

>That's why this position is
> interesting to use for testing positional understanding in a chess
> engine. Fritz10, of course, plays c5-c4. But how about Hiarcs11, Rybka,
> and other engines? Please test! You can either import the following as
> PGN, or copy and paste the FEN code.
>
>
> Mats
> -------------------------------------
>
> [Event "*"]
> [Site "?"]
> [Date "2007.08.16"]
> [White "Test position"]
> [Black "-"]
> [Result "*"]
> [SetUp "1"]
> [FEN "r1r2nk1/1bq1bppp/1p2p2n/2ppP3/3P4/pPP2N1P/P2Q1PP1/BBR1RNK1 b - - 0 1"]
> *
>
>

Date: 17 Aug 2007 07:02:56
From: M Winther
Subject: Re: Test position

Den 2007-08-17 01:36:45 skrev David Kane <[email protected] >:

>
> "M Winther" <[email protected]> wrote in message news:optw5eb7x53bzrao@kalroten...
>> Is there any chess program that, in the following test position,
>> avoids closing the position in this or the next move? Closing the
>> position with c5-c4 is very bad because white replies b3-b4 and then
>> black has no counterplay on the queen's flank. Although white's bishop
>> is closed in at a1, black also has a weakness at a3. White has the
>> king's flank to himself.
>>
>> No human player above 1300 in ELO would play c5-c4.
>
> This is certainly not true.1300's (and higher) make far more
> straightforward blunders than this.
>
>> It's a strategical
>> blunder of immense proportions.
>
> It would be educational for this player (somewhat >1300) to see actual analysis
> supporting the "White has the king's flank to himself" claim. Or an example of
> the "counterplay" when the Queenside isn't blocked.
>
> Computers aren't trying to mimic human preference, but to win. Do you
> beat these engines with Black before c4, or with White after c4 and b4?
> If so, it would be interesting to post your games.
>

David, "computers" generally seem to agree with me that Ng6 is better
than c5-c4, so I have no beef with them. However, as I expected, the
engines seem to overvalue c5-c4, i.e., it's not that bad.

Obviously c5-c4 is bad, I don't have to prove that in a superhuman way by
beating engines with grandmaster strength. It's bad because it cuts down
the strategical possibilities for black to a minimum. White, however, have
much better opportunities. Before c5-c4 black has a good position. After,
his strategical prospects are scarce.

Mats

Date: 17 Aug 2007 08:28:21
From: james
Subject: Re: Test position

M Winther a �crit :
> Den 2007-08-17 01:36:45 skrev David Kane <[email protected]>:
>
>>
>> "M Winther" <[email protected]> wrote in message
>> news:optw5eb7x53bzrao@kalroten...
>>> Is there any chess program that, in the following test position,
>>> avoids closing the position in this or the next move? Closing the
>>> position with c5-c4 is very bad because white replies b3-b4 and then
>>> black has no counterplay on the queen's flank. Although white's bishop
>>> is closed in at a1, black also has a weakness at a3. White has the
>>> king's flank to himself.
>>>
>>> No human player above 1300 in ELO would play c5-c4.
>>
>> This is certainly not true.1300's (and higher) make far more
>> straightforward blunders than this.
>>
>>> It's a strategical
>>> blunder of immense proportions.
>>
>> It would be educational for this player (somewhat >1300) to see actual
>> analysis
>> supporting the "White has the king's flank to himself" claim. Or an
>> example of
>> the "counterplay" when the Queenside isn't blocked.
>>
>> Computers aren't trying to mimic human preference, but to win. Do you
>> beat these engines with Black before c4, or with White after c4 and b4?
>> If so, it would be interesting to post your games.
>>
>
> David, "computers" generally seem to agree with me that Ng6 is better
> than c5-c4, so I have no beef with them. However, as I expected, the
> engines seem to overvalue c5-c4, i.e., it's not that bad.
>
> Obviously c5-c4 is bad, I don't have to prove that in a superhuman way by
> beating engines with grandmaster strength. It's bad because it cuts down
> the strategical possibilities for black to a minimum. White, however, have
> much better opportunities. Before c5-c4 black has a good position. After,
> his strategical prospects are scarce.
>
> Mats
Well, that is not that sure.
I tried a simple test. I set up the position after c4 and b4, and let
Fritz10 play black and rybka2.3.2 play white at tournament time control
(40 moves in 2 hours).
Well, evaluation by Fritz doesn't change and, believe it or not, Fritz
ends up winning the game by very slowly opening the game on the
queenside and letting white bishop trapped on a1.
What is an "evident mistake by a 1300 player" might not be a mistake for
a computer chess program, which has all the necessary patience and
computing power to exploit that kind of position...
The game is available here:

http://www.chess-lovers.org/fritz10/test.htm

Date: 17 Aug 2007 10:06:56
From: M Winther
Subject: Re: Test position

Den 2007-08-17 08:28:21 skrev james <[email protected] >:

> M Winther a �crit :
>> Den 2007-08-17 01:36:45 skrev David Kane <[email protected]>:
>>
>>>
>>> "M Winther" <[email protected]> wrote in message
>>> news:optw5eb7x53bzrao@kalroten...
>>>> Is there any chess program that, in the following test position,
>>>> avoids closing the position in this or the next move? Closing the
>>>> position with c5-c4 is very bad because white replies b3-b4 and then
>>>> black has no counterplay on the queen's flank. Although white's bishop
>>>> is closed in at a1, black also has a weakness at a3. White has the
>>>> king's flank to himself.
>>>>
>>>> No human player above 1300 in ELO would play c5-c4.
>>>
>>> This is certainly not true.1300's (and higher) make far more
>>> straightforward blunders than this.
>>>
>>>> It's a strategical
>>>> blunder of immense proportions.
>>>
>>> It would be educational for this player (somewhat >1300) to see actual
>>> analysis
>>> supporting the "White has the king's flank to himself" claim. Or an
>>> example of
>>> the "counterplay" when the Queenside isn't blocked.
>>>
>>> Computers aren't trying to mimic human preference, but to win. Do you
>>> beat these engines with Black before c4, or with White after c4 and b4?
>>> If so, it would be interesting to post your games.
>>>
>>
>> David, "computers" generally seem to agree with me that Ng6 is better
>> than c5-c4, so I have no beef with them. However, as I expected, the
>> engines seem to overvalue c5-c4, i.e., it's not that bad.
>>
>> Obviously c5-c4 is bad, I don't have to prove that in a superhuman way by
>> beating engines with grandmaster strength. It's bad because it cuts down
>> the strategical possibilities for black to a minimum. White, however, have
>> much better opportunities. Before c5-c4 black has a good position. After,
>> his strategical prospects are scarce.
>>
>> Mats
> Well, that is not that sure.
> I tried a simple test. I set up the position after c4 and b4, and let
> Fritz10 play black and rybka2.3.2 play white at tournament time control
> (40 moves in 2 hours).
> Well, evaluation by Fritz doesn't change and, believe it or not, Fritz
> ends up winning the game by very slowly opening the game on the
> queenside and letting white bishop trapped on a1.
> What is an "evident mistake by a 1300 player" might not be a mistake for
> a computer chess program, which has all the necessary patience and
> computing power to exploit that kind of position...
> The game is available here:
>
> http://www.chess-lovers.org/fritz10/test.htm
>
>

Thanks for this effort. I've analyzed the position more carefully now and,
obviously, the dead bishop on a1 remains a problem. Moreover, white
cannot easily put pressure on black's weak a-pawn. Probably I was
mistaken, then. I did not analyze the position properly, but, obviously,
a discussion group, as a concerted effort, could work
fine for once. It is interesting the way in which Fritz10 beat Rybka here.

Mats

Date: 16 Aug 2007 13:35:44
From: JeeBee
Subject: Re: Test position

Crafty 21.5 does recover from c4 in the intial position, however.
Unfortunately I want to restart X now, so I'll leave it like this.

17 -0.02 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd7 6. h4
{HT} (336.51)

17 -0.02 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd7 6. h4
{HT} (536.05)

18 +0.06 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd8 6. h4
Nxh4 7. Nxh7 Nf5 8. Qh3 Bg5 9. Rcd1 g6 10. Nxg5 Qxg5 (759.74)

18 +0.01 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rcb8 4. Qe3 c4 5. b4 Bc6 6. Bc2
Ba4 7. Bxa4 Rxa4 8. Rb1 Ra6 9. Ng5 Rab6 10. Kh1 (1226.21)

Date: 16 Aug 2007 13:08:49
From: JeeBee
Subject: Re: Test position

Here's what crafty 21.5 has to say about your position (first number is
depth, last number tells after how many seconds it has this principal
variation).

3 +0.04 1. ... Nf5 2. Ne3 Qd7 3. Nxf5 exf5 (0.01)

3 -0.15 1. ... Ba6 2. Ng3 Ng6 3. Bxg6 hxg6 (0.01)

3 -0.15 1. ... Ba6 2. Ng3 Ng6 3. Bxg6 hxg6 (0.02)

4 +0.00 1. ... Ba6 2. Ne3 Ng6 3. c4 (0.02)

4 +0.00 1. ... Ba6 2. Ne3 Ng6 3. c4 (0.03)

5 +0.05 1. ... Ba6 2. Ne3 cxd4 3. cxd4 Qd7 (0.03)

5 -0.09 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Bb5 4. Bxg6 hxg6 (0.05)

5 -0.09 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Bb5 4. Bxg6 hxg6 (0.06)

6 +0.04 1. ... Ng6 2. Ng3 Ba6 3. Bxg6 hxg6 4. Kh1 (0.07)

6 +0.04 1. ... Ng6 2. Ng3 Ba6 3. Bxg6 hxg6 4. Kh1 (0.12)

7 +0.01 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Kh8 4. Bxg6 hxg6 (0.16)

7 +0.01 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Kh8 4. Bxg6 hxg6 (0.22)

8 +0.00 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Kh1 (0.33)

8 +0.00 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Kh1 (0.53)

9 -0.05 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Qc2 f5 (0.68)

9 -0.05 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Qc2 f5 (0.83)

10 -0.01 1. ... Ng6 2. Ne3 c4 3. b4 Nh4 4. Nxh4 Bxh4 5. Bc2 Qe7 6. Kh1
(1.71)

10 -0.01 1. ... Ng6 2. Ne3 c4 3. b4 Nh4 4. Nxh4 Bxh4 5. Bc2 Qe7 6. Kh1
(2.83)

11 +0.01 1. ... Ng6 2. dxc5 Bxc5 3. Ng3 Ba6 4. Kh1 Be7 5. Rcd1 Qc5 6.
Nd4 Kh8 7. Bxg6 hxg6 (3.99)

11 +0.01 1. ... Ng6 2. dxc5 Bxc5 3. Ng3 Ba6 4. Kh1 Be7 5. Rcd1 Qc5 6.
Nd4 Kh8 7. Bxg6 hxg6 (5.19)

12 -0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 Bc6 5. Bxg6 hxg6 6. Rb1
Nf5 7. Qf4 (8.31)

12 -0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 Bc6 5. Bxg6 hxg6 6. Rb1
Nf5 7. Qf4 (9.72)

13 +0.01 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rab8 4. Bc2 {HT} (13.54)

13 +0.01 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rab8 4. Bc2 {HT} (19.82)

14 +0.02 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 {HT} (32.93)

14 +0.02 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 {HT} (52.82)

15 +0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rcb8 4. Qe3 Bc6 5. Rcd1 c4 6.
bxc4 dxc4 7. Bxg6 hxg6 8. Qf4 Bd5 (81.68)

15 -0.11 1. ... c4 2. bxc4 dxc4 3. Be4 Bxe4 4. Rxe4 Nf5 5. Ne3 Nxe3 6.
Qxe3 Ng6 7. Rb1 Rd8 8. Ng5 Rd5 (148.46)

15 -0.11 1. ... c4 2. bxc4 dxc4 3. Be4 Bxe4 4. Rxe4 Nf5 5. Ne3 Nxe3 6.
Qxe3 Ng6 7. Rb1 Rd8 8. Ng5 Rd5 (156.22)

16 -0.10 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd8 6. f4
Bc6 7. h4 Qd7 8. h5 Bxg5 9. fxg5 (207.44)

16 -0.10 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd8 6. f4
Bc6 7. h4 Qd7 8. h5 Bxg5 9. fxg5 (239.54)

--- Here I play c4 and b4 ---

...

12 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.31)

12 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.50)

13 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.51)

13 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (2.55)

14 -0.10 2. ... Nf5 3. Bxf5 exf5 4. Ng3 g6 5. Ng5 Qd8 6. h4 Ne6 7. Nxe6
fxe6 8. h5 gxh5 9. Nxh5 (12.15)

14 -0.10 2. ... Nf5 3. Bxf5 exf5 4. Ng3 g6 5. Ng5 Qd8 6. h4 Ne6 7. Nxe6
fxe6 8. h5 gxh5 9. Nxh5 (12.97)

15 +0.07 2. ... Nf5 3. g3 Nh6 4. h4 Bc6 5. h5 Ba4 6. Ne3 Nd7 7. g4 Qd8
8. Re2 Ra6 9. Kh1 Raa8 (52.99)

15 +0.07 2. ... Nf5 3. g3 Nh6 4. h4 Bc6 5. h5 Ba4 6. Ne3 Nd7 7. g4 Qd8
8. Re2 Ra6 9. Kh1 Raa8 (123.70)

16 +0.08 2. ... Nf5 3. g3 g6 4. h4 Qc6 5. Ne3 Nxe3 6. Qxe3 Nd7 7. Ng5 h6
8. Nxf7 Kxf7 9. Qxh6 Ke8 10. Bxg6+ Kd8 11. Qf4 (168.74)

16 +0.04 2. ... Qd8 3. g3 Bc6 4. Ne3 Nd7 5. Re2 Ba4 6. h4 Bb5 7. h5 Bg5
8. Rce1 Bxe3 9. Qxe3 Nf5 10. Bxf5 exf5 (195.98)

16 +0.04 2. ... Qd8 3. g3 Bc6 4. Ne3 Nd7 5. Re2 Ba4 6. h4 Bb5 7. h5 Bg5
8. Rce1 Bxe3 9. Qxe3 Nf5 10. Bxf5 exf5 (221.50)

Date: 17 Aug 2007 07:05:53
From: M Winther
Subject: Re: Test position

Den 2007-08-16 20:08:49 skrev JeeBee <[email protected] >:

> Here's what crafty 21.5 has to say about your position (first number is
> depth, last number tells after how many seconds it has this principal
> variation).
>
> 3 +0.04 1. ... Nf5 2. Ne3 Qd7 3. Nxf5 exf5 (0.01)
>
> 3 -0.15 1. ... Ba6 2. Ng3 Ng6 3. Bxg6 hxg6 (0.01)
>
> 3 -0.15 1. ... Ba6 2. Ng3 Ng6 3. Bxg6 hxg6 (0.02)
>
> 4 +0.00 1. ... Ba6 2. Ne3 Ng6 3. c4 (0.02)
>
> 4 +0.00 1. ... Ba6 2. Ne3 Ng6 3. c4 (0.03)
>
> 5 +0.05 1. ... Ba6 2. Ne3 cxd4 3. cxd4 Qd7 (0.03)
>
> 5 -0.09 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Bb5 4. Bxg6 hxg6 (0.05)
>
> 5 -0.09 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Bb5 4. Bxg6 hxg6 (0.06)
>
> 6 +0.04 1. ... Ng6 2. Ng3 Ba6 3. Bxg6 hxg6 4. Kh1 (0.07)
>
> 6 +0.04 1. ... Ng6 2. Ng3 Ba6 3. Bxg6 hxg6 4. Kh1 (0.12)
>
> 7 +0.01 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Kh8 4. Bxg6 hxg6 (0.16)
>
> 7 +0.01 1. ... Ng6 2. Ng3 Ba6 3. Kh1 Kh8 4. Bxg6 hxg6 (0.22)
>
> 8 +0.00 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Kh1 (0.33)
>
> 8 +0.00 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Kh1 (0.53)
>
> 9 -0.05 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Qc2 f5 (0.68)
>
> 9 -0.05 1. ... Ng6 2. Ne3 Nh4 3. Nxh4 Bxh4 4. Bd3 Qe7 5. Qc2 f5 (0.83)
>
> 10 -0.01 1. ... Ng6 2. Ne3 c4 3. b4 Nh4 4. Nxh4 Bxh4 5. Bc2 Qe7 6. Kh1
> (1.71)
>
> 10 -0.01 1. ... Ng6 2. Ne3 c4 3. b4 Nh4 4. Nxh4 Bxh4 5. Bc2 Qe7 6. Kh1
> (2.83)
>
> 11 +0.01 1. ... Ng6 2. dxc5 Bxc5 3. Ng3 Ba6 4. Kh1 Be7 5. Rcd1 Qc5 6.
> Nd4 Kh8 7. Bxg6 hxg6 (3.99)
>
> 11 +0.01 1. ... Ng6 2. dxc5 Bxc5 3. Ng3 Ba6 4. Kh1 Be7 5. Rcd1 Qc5 6.
> Nd4 Kh8 7. Bxg6 hxg6 (5.19)
>
> 12 -0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 Bc6 5. Bxg6 hxg6 6. Rb1
> Nf5 7. Qf4 (8.31)
>
> 12 -0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 Bc6 5. Bxg6 hxg6 6. Rb1
> Nf5 7. Qf4 (9.72)
>
> 13 +0.01 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rab8 4. Bc2 {HT} (13.54)
>
> 13 +0.01 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rab8 4. Bc2 {HT} (19.82)
>
> 14 +0.02 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 {HT} (32.93)
>
> 14 +0.02 1. ... Ng6 2. dxc5 bxc5 3. Ng3 c4 4. b4 {HT} (52.82)
>
> 15 +0.04 1. ... Ng6 2. dxc5 bxc5 3. Ng3 Rcb8 4. Qe3 Bc6 5. Rcd1 c4 6.
> bxc4 dxc4 7. Bxg6 hxg6 8. Qf4 Bd5 (81.68)
>
> 15 -0.11 1. ... c4 2. bxc4 dxc4 3. Be4 Bxe4 4. Rxe4 Nf5 5. Ne3 Nxe3 6.
> Qxe3 Ng6 7. Rb1 Rd8 8. Ng5 Rd5 (148.46)
>
> 15 -0.11 1. ... c4 2. bxc4 dxc4 3. Be4 Bxe4 4. Rxe4 Nf5 5. Ne3 Nxe3 6.
> Qxe3 Ng6 7. Rb1 Rd8 8. Ng5 Rd5 (156.22)
>
> 16 -0.10 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd8 6. f4
> Bc6 7. h4 Qd7 8. h5 Bxg5 9. fxg5 (207.44)
>
> 16 -0.10 1. ... c4 2. b4 Nf5 3. Ne3 Nxe3 4. Qxe3 Ng6 5. Ng5 Qd8 6. f4
> Bc6 7. h4 Qd7 8. h5 Bxg5 9. fxg5 (239.54)
>
> --- Here I play c4 and b4 ---
>
> ...
>
> 12 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.31)
>
> 12 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.50)
>
> 13 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (0.51)
>
> 13 -0.02 2. ... Nf5 3. Bxf5 exf5 {HT} (2.55)
>
> 14 -0.10 2. ... Nf5 3. Bxf5 exf5 4. Ng3 g6 5. Ng5 Qd8 6. h4 Ne6 7. Nxe6
> fxe6 8. h5 gxh5 9. Nxh5 (12.15)
>
> 14 -0.10 2. ... Nf5 3. Bxf5 exf5 4. Ng3 g6 5. Ng5 Qd8 6. h4 Ne6 7. Nxe6
> fxe6 8. h5 gxh5 9. Nxh5 (12.97)
>
> 15 +0.07 2. ... Nf5 3. g3 Nh6 4. h4 Bc6 5. h5 Ba4 6. Ne3 Nd7 7. g4 Qd8
> 8. Re2 Ra6 9. Kh1 Raa8 (52.99)
>
> 15 +0.07 2. ... Nf5 3. g3 Nh6 4. h4 Bc6 5. h5 Ba4 6. Ne3 Nd7 7. g4 Qd8
> 8. Re2 Ra6 9. Kh1 Raa8 (123.70)
>
> 16 +0.08 2. ... Nf5 3. g3 g6 4. h4 Qc6 5. Ne3 Nxe3 6. Qxe3 Nd7 7. Ng5 h6
> 8. Nxf7 Kxf7 9. Qxh6 Ke8 10. Bxg6+ Kd8 11. Qf4 (168.74)
>
> 16 +0.04 2. ... Qd8 3. g3 Bc6 4. Ne3 Nd7 5. Re2 Ba4 6. h4 Bb5 7. h5 Bg5
> 8. Rce1 Bxe3 9. Qxe3 Nf5 10. Bxf5 exf5 (195.98)
>
> 16 +0.04 2. ... Qd8 3. g3 Bc6 4. Ne3 Nd7 5. Re2 Ba4 6. h4 Bb5 7. h5 Bg5
> 8. Rce1 Bxe3 9. Qxe3 Nf5 10. Bxf5 exf5 (221.50)
>

He regards it as equal then. Just as I expected, today's engines, not even Rybka, have
an effective way of thinking strategically. This weakness could be utilized by human
grandmasters.

Mats

Date:
From: Martin Brown
Subject: Re: Test position

Date: 16 Aug 2007 16:53:23
From: M Winther
Subject: Re: Test position

Den 2007-08-16 14:23:32 skrev tin Brown <

Date: 16 Aug 2007 16:59:16
From: M Winther
Subject: Re: Test position

Correction. This is the correct PGN:

[Event "*"]
[Site "?"]
[Date "2007.08.16"]
[White "Test position 2"]
[Black "-"]
[Result "*"]
[SetUp "1"]
[FEN "r1r2nk1/1bq1bppp/1p2p2n/3pP3/1PpP4/p1P2N1P/P2Q1PP1/BBR1RNK1 b - - 0 2"
*