Author: Robert Hyatt
Date: 19:56:34 09/13/01
Go up one level in this thread
On September 13, 2001 at 17:59:44, Uri Blass wrote:
>On September 13, 2001 at 17:26:21, K. Burcham wrote:
>
>>[Event "IBM Kasparov vs. Deep Blue Rematch"]
>>[Site "New York, NY USA"]
>>[Date "1997.05.04"]
>>[Round "2"]
>>[White "Deep Blue"]
>>[Black "Kasparov, Garry"]
>>[Opening "Ruy Lopez: closed, Smyslov defense"]
>>[ECO "C93"]
>>[Result "1-0"]
>>
>>1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 d6
>>8.c3 O-O 9.h3 h6 10.d4 Re8 11.Nbd2 Bf8 12.Nf1 Bd7 13.Ng3 Na5 14.Bc2 c5
>>15.b3 Nc6 16.d5 Ne7 17.Be3 Ng6 18.Qd2 Nh7 19.a4 Nh4 20.Nxh4 Qxh4
>>21.Qe2 Qd8 22.b4 Qc7 23.Rec1 c4 24.Ra3 Rec8 25.Rca1 Qd8 26.f4 Nf6
>>27.fxe5 dxe5 28.Qf1 Ne8 29.Qf2 Nd6 30.Bb6 Qe8 31.R3a2 Be7 32.Bc5 Bf8
>>33.Nf5 Bxf5 34.exf5 f6 35.Bxd6 Bxd6 36.axb5 axb5 37.Be4 Rxa2
>>38.Qxa2 Qd7 39.Qa7 Rc7 40.Qb6 Rb7 41.Ra8+ Kf7 42.Qa6 Qc7 43.Qc6 Qb6+
>>44.Kf1 Rb8 45.Ra6 1-0
>>
>>last book move for shredder 5 was 19. a4.
>>so from move 20 to final white move of 45. Ra6, deep blue had 25 moves.
>>of the 25 deep blue moves, shredder5 chose 20. 80% of deep blue moves chosen.
>>GT.2 was almost identical to this.
>>
>>of the 24 GM moves , after book, shredder5 chose 14 moves. for 58% of GM
>> moves.
>>
>>two significant moves 26.f4 and 37. Be4.
>>todays programs can find both of these moves in tournament time.
>>
>>OF COURSE THE MOST SIGNIFICANT MOVE. 45...Qe3.
>>with this move kasparov had several combinations to draw.
>>but instead kasparov resigned. he did not see the draw
>> that todays programs are very capable of playing.
>>
>>so the following is some of the commentary during the game.
>>you can see these commentators did not anticipate the possible
>>draw with 45...Qe3, or the resign from kasparov.
>>also you will notice kasparov had 58 minutes remaining.
>>
>>Patrick Wolff wants to play 45...Ra8.
>>kasparov wants to resign. which he did.
>>here is the final position.
>>
>> [D] 1r6/5kp1/RqQb1p1p/1p1PpP2/1Pp1B3/2P4P/6P1/5K2 b - -
>>
>>
>>
>>
>>MAURICE ASHLEY: As we take a look at the clock it seems like Kasparov has more
>>time than the computer does, than Deep Blue does because he has 58 minutes
>>remaining and Deep Blue has 23 minutes remaining. That is in fact not true. The
>>one at the bottom of the screen, the /TK-P side shows it's still in that first
>>time control, while Garry is in the second time control, you see the two. So
>>Garry has 58 moves remaining until move 60 while Deep Blue has in fact an hour
>>and 23 minutes remaining on its clock. And that would be -- that will be
>>revealed as soon as it passes the 00 mark. So plenty of time for both sides. And
>>the game -- it's heating up. I mean a mate threat has occurred. And that
>>suggests certain actions, definite things are beginning to occur. Garry has to
>>be very precise in his decision-making or else he could easily mind himself just
>>completely lost instantly
>>
>>
>>
>>PATRICK WOLFF: My point being, if we go all the way down here. I want to make
>>two points. First of all, this is Kasparov's last line of defense. The last line
>>of defense is what we call perpetual check. Continually checking the opponent's
>>king. There's no danger of checkmate. That's why it's call perpetual check, but
>>it goes on forever, it's perpetual, and because it's continually check, check,
>>check, check, check, check, check, the game could be a draw. Whether or not this
>>is perpetual check requires very, very precise analysis.
>>
>>YASSER SEIRAWAN: d5xc6, absolutely.
>>
>> YASSER SEIRAWAN: I think that the ending, when the pawn is on d5, the ending
>>with the pawn on d5, black has excellent holding chances. With the pawn on c6, I
>>think he's gone. This is a very bad pawn. Because with a pawn on c6, white's
>>bishop will be able to go to the d5 square check. The e6 square, and then when
>>he moves Ra7 and c7 he will just win a piece and the game. So after this what
>>appears to be a forced exchange of queens, I don't see how Garry is going to
>>defend.
>>
>>PATRICK WOLFF: Exactly. Let's take a look at Rc8. Now, the idea of Rc8 is white
>>was threatening this check. Now, if that check should happen, black can block it
>>with the rook. But I think we'll see that there's still a lot of trouble for
>>black here. Ra7+ I think is still very strong. Now, Bc7 is very bad because
>>white plays Rb7. Black cannot defend like that, because that guy goes. So after
>>rook b7 this b5 pawn is in bad shape. Therefore, after Ra7+, Rc7 is pretty much
>>forced. But now we play Ra8.
>>
>>YASSER SEIRAWAN: Ra5.
>>
>>PATRICK WOLFF: Also Ra5, good point. Itself going to -- I was going to suggest
>>that black would be tied up with Ra8, but that would be bad enough, but
>>
>>YASSER is correct.
>>
>>MAURICE ASHLEY: And looking at Garry Kasparov now, he does not look like a happy
>>man. He has all these variations --
>>
>>{{as you can see by the above conversation, Yasser did not anticipate the
>> resign in this position. and also not only did kasporov miss the
>> 45...Qe3 for the draw, Yasser missed the draw also.}}
>>
>>
>>this is one of the drawn positions, that kasparov could have played into
>> with, 45...Qe3. instead as you can read Mr. Ashleys words,
>> kasparov resigned the position.
>>
>> [D] 4r3/5kp1/R2Q1p2/1p1Pp2p/1Pp4q/5B2/5KP1/8 w - -
>>
>>
>>MAURICE ASHLEY: Garry Kasparov has resigned the position. (Audience applause.)
>>(Long and sustained audience applause.)
>>
>>MAURICE ASHLEY: We were indeed impressed by the way the computer handled this
>>position. We hope, we'll cross our fingers, but don't count on it that Garry
>>will come on stage and explain why he lost. I don't think so.
>>
>> MIKE VALVO: Several Grandmasters were astounded by this game. It's clearly the
>>best game ever played against Kasparov by a computer.
>>
>>YASSER SEIRAWAN: The question was, during the game, was there ever a negative
>>valuation. In other words, did Deep Blue ever feel itself to have a worse
>>position at any time, and what was the final position. JOEL BENJAMIN: Short
>>answer, no, it always felt that it had a slight advantage, until near the end
>>when it felt it had a larger advantage, and then the score in the last few moves
>>went very high and it was something like two pawns up.
>>
>>
>>Question for Dr Hyatt: in the final position, Joel Benjamin said deep blue
>> eval was close to +2.00. shredder5 finds 45...Qe3 in 30 seconds with
>> 1500 mhz. eval starts out at +1.88, with shredder5, and drops quickly.
>>in 3 minutes shredder5 eval drops to +1.40. in 15 minutes shredder5 eval
>>drops to +1.26. i do not understand how deep blue eval can be +2.00.
>>deep fritz and GT2.0 are similiar in this 45...Qe3 eval. if deep blue
>>was so far ahead of these rpograms in kns, it seems in this final position
>>that deep blue eval should be somewhat lower than +2.00 for 45...Qe3,
>>you would think in this position deep blue could see the drawn position
>> of 45...Qe3. and if you say it could see the draw, then why did Joel
>> say eval was close to +2.00.
>
>My opinion is that deeper blue simply had inferior evaluation in that position.
>
>If you try older programs like Genius3 and even Junior6 then they also cannot
>see Qe3 in a reasonable time.
>
>Hyatt claimed that no program including deeper blue can see the draw.
>I agree that the top programs do not see 0.00 score for Qe3 and the score is
>dependent on evaluation.
>
>The question if to evaluate Qe3 as +2.xx or +1.xx is also dependent in the value
>that chess programs give to pawns and if you reduce the value of pawns you are
>going to find that finding Qe3 with better score than 2 pawns against black is
>hard task for chess programs.
>
>Uri
How can you compare the scores from two programs that likely have different
values for pawns? I know deep thought used 1.28 for a pawn's value. It is
most likely that Deep Blue kept that. I have no idea what Shredder uses, but
I have heard that some programs drop the value of a pawn as low as .75.
2 * .75 = 1.50
2 * 1.28 = 2.56
yet both are ahead two pawns. I don't think the absolute value of the score is
the important thing. Comparing the evals of two different programs is like
comparing body parts. They can all be different sizes and shapes, but they
can accomplish the same functions.
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