Author: Ingo Althofer
Date: 22:14:14 10/16/02
Go up one level in this thread
On October 16, 2002 at 17:07:19, GuyHaworth wrote:
>The Bib page merely replicates the analysis referred to
>by Richard Bean in "kasparov on possible draw in game 6"
>... note 'possible'.
>
>As I understand Russian even less than chess, I'm
>waiting for some authoritative comment on this
>'possible draw' ....
We speak about the situation after Kramnik's possible
move 35.Rxa6 and the resulting position
White: Kg1, Ra6, Re1, Pf2, Pg3;
Black: Kg7, Rc8, Nd5, Ph7, Pb6, Pb3;
Black to move.
It seems impossible to prove a draw by complete game
tree search. Especially, at move 40... there are several
alternatives instead of ...Qf5 which makes the tree
very bushy and large.
However, here comes a new argument why Kramnik would have
had almost 100 percent practical drawing chances in Bahrain:
It seems that Fritz and also many other chess programs do
not understand the character of the position. I replayed
the endgame with Shredder6.02 for both sides, on a 900
MHz PC (Athlon), with 30 seconds per move.
Please, skip the resulting output and jump to the end
of the page when you don't like details.
The file reads as follows (for each move):
move Shredder-evaluation/seaarch depth time in seconds
I did not do renumbering, so move 1 in this file is move 35
in the Bahrain game, and so on.
1... b2 -4.23/14 30
2.Ta7+ -4.25/14 31 Kg6 -4.34/13 30
3.Td7 -4.21/14 31 Tc1 -4.21/15 30
4.Td6+ -4.18/16 30 Sf6 -4.13/17 31
5.Tdd1 -4.13/16 31 b1D -4.13/15 31
6.Txc1 -4.20/12 31 Df5 -4.17/12 31
7.Tc6 -3.98/13 30 b5 -3.78/13 31
8.Tee6 -3.88/13 31 b4 -3.88/13 31
9.Tb6 -3.90/13 30 Kf7 -3.90/12 31
10.Tec6 -3.66/12 30 Db1+ -3.18/11 31
11.Kh2 -2.92/12 31 Sd7 -2.69/12 31
12.Tb7 -2.36/13 31 Ke7 -2.35/13 31
13.Tc4 -2.47/13 31 Df1 -2.68/13 31
14.Te4+ -2.82/13 31 Kd6 -3.01/13 31
15.Td4+ -3.01/13 32 Kc6 -3.01/13 31
16.Tdxd7 -3.29/13 31 Dxf2+ -3.29/13 31
17.Kh1 -3.41/13 31 Dxg3 -3.42/13 31
18.Tg7 -3.66/12 31 Dh3+ -3.66/12 31
19.Kg1 -3.66/13 2 h5 -3.66/12 31
20.Tgc7+ -3.74/10 33 Kd6 -3.79/12 34
21.Tg7 -3.88/12 31 b3 -3.94/12 31
22.Tg6+ -3.79/11 30 Ke5 -3.54/13 31
23.Tgb6 -3.53/13 31 Dg3+ -3.50/12 31
24.Kf1 -3.45/14 31 Df3+ -3.45/12 31
25.Kg1 -3.44/13 31 Dg3+ -3.45/14 31
26.Kf1 -3.20/14 31 Df3+ -3.19/12 31
27.Kg1 -2.94/12 30 De3+ -2.94/12 31
28.Kf1 -2.94/13 31 Dd3+ -2.94/13 31
29.Kg2 -2.94/13 30 De2+ -2.94/13 30
30.Kg3 -2.69/13 31 Dg4+ -2.21/11 31
31.Kf2 -1.96/12 30 Dd4+ -1.61/12 32
32.Kg2 -1.61/13 31 Dg4+ -1.61/13 31
33.Kh2 -1.61/13 30 Df4+ -1.38/13 31
34.Kg2 -1.37/14 31 Dg4+ -1.37/13 30
35.Kh2 -1.37/14 31 Df4+ -1.37/13 30
36.Kg1 -1.37/14 30 Dd4+ -1.37/14 31
37.Kh2 -1.37/14 30 Df2+ -1.36/12 31
38.Kh3 -1.36/14 30 Df5+ -1.36/13 31
39.Kh2 -1.36/14 31 Df2+ -1.36/13 31
40.Kh3 -1.15/13 30 b2 -1.14/11 31
41.Tb5+ -1.24/12 30 Kd4 -1.21/14 30
42.Tb4+ -1.21/13 30 Kd5 -1.09/14 30
43.T4b5+ -1.07/14 30 Kd4 -0.97/13 31
44.Tb4+ -1.07/14 31 Kc5 -1.07/14 31
45.Txb2 -1.03/14 30 Df3+ -1.22/12 30
46.Kh2 -1.21/13 31 Df4+ -1.19/13 31
47.Kg1 -1.19/13 31 Dd4+ -1.00/12 30
48.Kh2 -0.96/13 30 Df4+ -0.96/13 30
49.Kg2 -0.96/14 30 Dg4+ -0.96/14 31
50.Kh2 -0.96/13 31 Dh4+ -0.96/13 31
51.Kg2 -0.87/14 30 De4+ -0.87/13 31
52.Kh2 -0.60/13 30 Dh4+ -0.60/12 31
session stopped by the operator
*********************************************
Now comes the new argument. I do not have the
complete Bahrain rules at hand, but Eric Schiller
(who was planned to be one of two arbiters
in Bahrain - but was rejected in June 2002)
made the following version public which was agreed
on in September 2001 and was still valid in June 2002:
...
8.4 Draw Offers
1...
2...
3.If Mr. Kramnik feels that the position is clearly drawn,
he may notify the Arbiter and the Operator that he is
making a claim of "technical draw". The Arbiter will stop
the clock. Mr. Kramnik will then explain his reasoning,
and theOpertor is obliged to accept the draw unless Fritz
can demonstrate that in the previous ten moves, progress
has been made.
4...
Here, the crucial point is that Fritz has to demonstrate that
IN THE LAST TEN MOVES progress has been made.
Now you may look back into the Shredder file above:
According to Shredder's evaluations there was for instance
no progress between moves 22 and 32. So, Kramnik might have
claimed a technical draw already at this point.
Ingo Althofer.
PS: I don't like this rule 8.4.3, but it seems to be reality.
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