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Subject: Re: Endgame Position : What do Fritz 8 and Shredder 7 say?

Author: Roy Brunjes

Date: 14:20:55 01/01/03

Go up one level in this thread


On January 01, 2003 at 12:59:22, Christopher A. Morgan wrote:

>
>Your FEN should be: 5k2/7p/6p1/1p3p2/5P2/5P2/PPr4P/5KR1 b - -, that is black to
>move, not white.

Of course you are correct -- my diagram showed White to move and it was Black to
move.  Sorry!

>
>Shredder 7 sees ...Rxh2 almost immediately, while Fritz 8 sees it immediately,
>both on Athlon 750 with 96MB hash.
>
>New game
>5k2/7p/6p1/1p3p2/5P2/5P2/PPr4P/5KR1 b - - 0 1
>
>Analysis by Shredder 7:
>
>1...Rxb2
>  ì  (-1.26)   Depth: 1/1   00:00:00
>1...Rxb2
>  ì  (-1.26)   Depth: 1/1   00:00:00
>1...Rxb2 2.Rg2
>  ì  (-1.30)   Depth: 2/4   00:00:00
>1...Rxh2 2.Rg4
>  ì  (-1.32)   Depth: 2/4   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2
>  ì  (-1.39)   Depth: 2/4   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2
>  ì  (-1.39)   Depth: 3/4   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5
>  -+  (-1.66)   Depth: 4/5   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5
>  -+  (-1.66)   Depth: 4/6   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.Kg3
>  -+  (-1.67)   Depth: 5/10   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.Kg3 Ke7
>  -+  (-1.79)   Depth: 6/9   00:00:00
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.b3 Ke7 5.a4
>  -+  (-1.81)   Depth: 7/11   00:00:00  5kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.b3 b4 5.Kg3 Ke7
>  -+  (-1.80)   Depth: 8/14   00:00:00  13kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.a3 Ke7 5.Kg3 Ke6 6.b3
>  -+  (-1.91)   Depth: 9/13   00:00:00  26kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 h5 4.a3 Ke7 5.Kg3 Ke6 6.b3 Kd5
>  -+  (-1.87)   Depth: 10/15   00:00:00  43kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd8 5.Kg3 h5 6.b3 Ke7 7.a4
>  -+  (-1.62)   Depth: 11/14   00:00:00  71kN
>1...Rxh2 2.Rg2 Rh4 3.Kf2 Rxf4 4.b3 Ke7 5.Ke3 Rh4 6.a3 Ke6
>  ì  (-1.34)   Depth: 11/18   00:00:01  150kN
>1...Rxh2 2.Rg2 Rh4 3.Kf2 Rxf4 4.b3 Rh4 5.a3 Ke7 6.Ke3 Ke6 7.Rd2
>  ì  (-1.39)   Depth: 12/19   00:00:02  294kN
>1...Rxh2 2.Rg2 Rh4 3.Kf2 Rxf4 4.b3 Rh4 5.a3 Ke7 6.Ke3 Ke6 7.Rd2 g5
>  -+  (-1.45)   Depth: 13/21   00:00:03  523kN
>1...Rxh2 2.Rg2 Rh4 3.Re2 Rxf4 4.Kg2 Rd4 5.Kg3 Rd5 6.b3 b4 7.Rc2 h6 8.Rc7
>  ì  (-1.40)   Depth: 14/23   00:00:05  1032kN, tb=1
>1...Rxh2 2.Rg2 Rh4 3.Rc2 Rxf4 4.Kg2 Rd4 5.Kg3 h5 6.Rc5 b4 7.a4 bxa3 8.bxa3 Ke7
>  ì  (-1.36)   Depth: 15/23   00:00:10  2093kN, tb=5
>1...Rxh2 2.Rg2 Rh4 3.Rc2 Rxf4 4.Kg2 Rd4 5.Kg3 h5 6.Rc5 Rb4 7.b3 Ke7
>  ì  (-1.30)   Depth: 16/25   00:00:17  3409kN, tb=41
>1...Rxh2 2.Rg2 Rh4 3.Rc2 Rxf4 4.Kf2 h5 5.Rc5 Rb4 6.b3 Ke7 7.Rc6 Kf7 8.Kg2
>  -+  (-1.50)   Depth: 17/29   00:00:38  7792kN, tb=184
>1...Rxh2 2.Rg2 Rh4 3.Rd2 Rxf4 4.Kg2 Ke7 5.Kg3 Rb4 6.b3 h5 7.Rd3 Kf6 8.a3 Ke6
>  -+  (-1.46)   Depth: 18/30   00:01:33  18691kN, tb=1151
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Ke6 5.b3 Kd5 6.Kg3 Kd4 7.Kh3 Kc3 8.a4 Kb4
>9.Kg2 bxa4 10.Kg1
>  ì  (-1.35)   Depth: 19/31   00:02:09  26368kN, tb=1782
>
>
>New game
>5k2/7p/6p1/1p3p2/5P2/5P2/PPr4P/5KR1 b - - 0 1
>
>Analysis by Fritz 8:
>
>1...Rxh2!
>  -+  (-2.44)   Depth: 7/16   00:00:00  12kN
>1...Rxh2 2.b3 Rxa2 3.Rg3
>  -+  (-2.59)   Depth: 7/16   00:00:00  15kN
>1...Rxh2 2.b4 Rxa2 3.Rg3 Rb2 4.Rh3
>  -+  (-2.69)   Depth: 8/16   00:00:00  32kN
>1...Rxh2 2.b3 Rxa2 3.Rg3 Rb2 4.Rh3 Kg7 5.b4 Rxb4
>  -+  (-2.75)   Depth: 9/21   00:00:00  66kN
>1...Rxh2--
>  -+  (-2.47)   Depth: 10/18   00:00:00  115kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 h6 6.a4 b4 7.Kf2 Kd5
>  -+  (-2.34)   Depth: 10/18   00:00:00  131kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 h6 6.a4 bxa4 7.bxa4 Kc5 8.Kg3 Kb4
>  -+  (-2.41)   Depth: 11/19   00:00:00  255kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 h6 6.a4 bxa4 7.bxa4 Kc5 8.Kg3 Kb4
>  -+  (-2.41)   Depth: 12/20   00:00:01  446kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 h6 6.Kf2 Kd5 7.a4 Kd4 8.axb5 Kc5
>9.Ke3
>  -+  (-2.31)   Depth: 13/22   00:00:03  887kN
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 Kc5 6.Kf2 Kd4 7.a4 b4 8.Kg3 h6
>9.Kh4
>  -+  (-2.44)   Depth: 14/27   00:00:05  1779kN, tb=1
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 h6 6.Kf2 Kc6 7.Ke3 Kc5 8.Kd3 Kb6
>9.a4 bxa4
>  -+  (-2.44)   Depth: 15/24   00:00:10  3202kN, tb=3
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 Kd5 6.Kf2 Kd4 7.a4 b4 8.Kg3 h6
>9.Kh3 Kd5
>  -+  (-2.38)   Depth: 16/28   00:00:17  5959kN, tb=17
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.a3 Kd6 5.b3 Kd5 6.Kf2 Kd4 7.a4 b4 8.Kg3 h6
>9.Kh3 Kd5
>  -+  (-2.38)   Depth: 17/29   00:00:36  13577kN, tb=47
>1...Rxh2!
>  -+  (-2.66)   Depth: 18/35   00:01:01  23063kN, tb=76
>1...Rxh2 2.Rg2 Rxg2 3.Kxg2 Ke7 4.Kf2 Kd6 5.Ke3 Kd5 6.Kd2 Kc4 7.Ke3 h6
>  -+  (-2.63)   Depth: 19/41   00:02:06  46431kN, tb=578
>
>
>

Both Shredder 7 and Fritz 8 are impressive here.  Fritz 8 slightly more so as it
spots the relevant line sooner than Shredder 7.

Thanks for the data!

Roy

>
>On January 01, 2003 at 11:41:37, Roy Brunjes wrote:
>
>>I came across this endgame in a software course I am using for chess training.
>>I gave the position to Hiarcs 8, Junior 7, and Chessmaster 9000 and they seem to
>>miss the point.  I am wondering what Fritz 8 and Shredder 7 have to say about
>>it.
>>
>>[D] 5k2/7p/6p1/1p3p2/2r2P2/5P2/PP5P/5K1R b - -
>>
>>In this position, with Black to move, Rc2 is the stated best move.  I have no
>>argument with that and neither do any of the programs I tried.  The rub comes
>>after this:
>>
>>1. ...  Rc2
>>2. Rg1
>>
>>Which gives this position:
>>
>>[D] 5k2/7p/6p1/1p3p2/5P2/5P2/PPr4P/5KR1 w - -
>>
>>Now White is attempting to activate his rook.  Programs I have tried (listed
>>above) all want to play 2. ... Rxb2 after searches running for 3-4 minutes
>>(admiteddly on my slow PIII 500 MHz laptop).  This leads to a much more
>>difficult ending that Hiarcs 8 was unable to win against me (and I'm a Class C
>>player) at a time control of 10 mins + 10 secs per move.  That tells me that the
>>move Rxb2 is probably not best.
>>
>>The training software says 2. ... Rxb2 is a mistake and instead recommends 2.
>>... Rxh2!
>>
>>Then, after 2. ... Rxh2 comes 3. Rg2 Rxg2 4. Kxg2.  Now both sides bring Kings
>>to the center and Black must use his passed pawn on the h file to distract the
>>White King from his job of keeping Black's King away from his pawns on a2 and
>>b2.  Once the White King is forced to head toward the Black h pawn, the invasion
>>of the Black King wins the game.
>>
>>My question is this:  What programs will play 2. ... Rxh2?  And 3. ... Rxg2
>>[after 3. Rg2 by White] instead of 3. ... Rh4, and after how much time?
>>Chessmaster 9000 wants to play 2. ... Rxh2 for a bit but then opts for 2. ...
>>Rxb2 instead after a search of 7/12 ply.  It seems to stick with that for quite
>>a while and then finally changes back to 2. ... Rxh2 at ply 10/15 (4 minutes 25
>>seconds on my old, slow PIII-500 laptop).
>>
>>It seems to me that the principles are pretty clear and that a good endgame
>>playing program should not need huge amounts of CPU time to select the right
>>plan.
>>
>>Thanks in advance for putting Fritz 8 and Shredder 7 to the test.  Feel free to
>>try it with other programs as well -- I have particular interest in those two
>>however as they are newer and I have no access to them.  So far, only CM9000
>>does find the right sequence of moves, though it takes quite a few ply to do so.
>> Yes, of course my faster computers would get there quicker, but still, they
>>will require just as many ply to see the win.  I would have thought a program
>>with lots of endgame knowledge could spot the win fairly quickly.
>>
>>Lastly, Happy New Year to all CCC readers!
>>
>>Roy



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