Author: Steffen Jakob
Date: 08:52:28 05/27/99
Go up one level in this thread
On May 27, 1999 at 11:32:55, KarinsDad wrote:
>The thought occurred to me that there are positions which are drawn due to
>massive pawn chains that prevent either king from entering into the opponent's
>position and hence, prevent any improvement for either side.
>
>Granted, positions like these (and I do not have an example) will result in an
>eventual draw by repetition or draw by 50 move rule, however, I was curious
>whether any of the chess programs detect a draw way before this occurs.
Look at this position:
4k3/8/1p1p4/pPpPp1p1/P1P1PpPp/5P1P/2BB4/K7 b
I implemented an idea in Hossa which doesnt look at the static score only but
also how the score changed in the last moves. The idea is that if you have a
huge advantage in material then you should be able to improve your position in
some moves. If you can't do this and moreover the weaker side doesn't even have
.to change his position a lot then it's very likely that there is a blocked
position and that you can adjust the score.
Here is the evaluation of Hossa with the blocked position evaluation enabled:
+---+---+---+---+---+---+---+---+
8 | | | | ||K|| | | |
+---+---+---+---+---+---+---+---+ Black: Hossa v1.54 (C) (0)
7 | | | | | | | | |
+---+---+---+---+---+---+---+---+ Black material: 8
6 | ||P|| ||P|| | | | |
+---+---+---+---+---+---+---+---+
5 ||P|| P ||P|| P ||P|| ||P|| |
+---+---+---+---+---+---+---+---+ Black to move
4 | P | | P | | P ||P|| P ||P||
+---+---+---+---+---+---+---+---+
3 | | | | | | P | | P |
+---+---+---+---+---+---+---+---+ White material: 14.62
2 | | | B | B | | | | |
+---+---+---+---+---+---+---+---+ White: opponent (0)
1 | K | | | | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
FEN: 4k3/8/1p1p4/pPpPp1p1/P1P1PpPp/5P1P/2BB4/K7 b
Position ID: "blocked position"
1 -7.74 0.06 6 1... e8f7
<1> -7.74 0.06 10 1... e8f7
2 -7.85 0.06 32 1... e8f7 2.a1b2
<2> -7.85 0.07 67 1... e8f7 2.a1b2
3 -7.83 0.07 156 1... e8f7 2.a1b2 f7f6
<3> -7.83 0.07 197 1... e8f7 2.a1b2 f7f6
4 -7.87 0.10 527 1... e8f7 2.a1b2 f7f6 3.c2d3
<4> -7.87 0.13 632 1... e8f7 2.a1b2 f7f6 3.c2d3
5 -7.89 0.15 1296 1... e8f7 2.a1b2 f7f6 3.c2d3 f6f7
5/5 -7.87 0.20 2939 1... e8e7 2.a1b2 e7f7 3.c2d3 f7f6
<5> -7.87 0.21 2939 1... e8e7 2.a1b2 e7f7 3.c2d3 f7f6
6 -7.91 0.26 5395 1... e8e7 2.a1b2 e7f7 3.c2d3 f7f6
4.d2c3
<6> -7.91 0.30 6003 1... e8e7 2.a1b2 e7f7 3.c2d3 f7f6
4.d2c3
7 -7.91 0.38 11125 1... e8e7 2.a1b2 e7f6 3.c2d3 f6f7
4.d2c3 f7f6
<7> -7.91 0.42 11390 1... e8e7 2.a1b2 e7f6 3.c2d3 f6f7
4.d2c3 f7f6
! 8 1/2 0.79 47883 1... e8e7 2.a1b2 e7d7 3.d2xa5 b6xa5
4.c2d3 d7c7 5.b6 c7xb6
! <8> 1/2 0.83 48001 1... e8e7 2.a1b2 e7d7 3.d2xa5 b6xa5
4.c2d3 d7c7 5.b6 c7xb6
9 1/2 1.45 97113 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7
<9> 1/2 1.49 97117 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7
10 1/2 2.01 153481 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1xa5 b6xa5
<10> 1/2 2.05 153485 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1xa5 b6xa5
11 1/2 3.22 263511 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
<11> 1/2 3.26 263515 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
12 1/2 4.52 416434 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.f2xc5 b6xc5
<12> 1/2 4.56 416438 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.f2xc5 b6xc5
13 1/2 6.91 640358 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7
<13> 1/2 6.94 640362 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7
14 1/2 9.35 915370 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7 8.f2xh4 g5xh4
<14> 1/2 9.41 915374 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7 8.f2xh4 g5xh4
15 1/2 13.14 1327765 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7 8.d1e2 c7d7
<15> 1/2 13.19 1327769 1... e8e7 2.a1b2 e7d7 3.c2d1 d7c7
4.b2c2 c7d7 5.d2e1 d7c7 6.e1f2 c7d7
7.c2d3 d7c7 8.d1e2 c7d7
Unfortunately there are some technical problems like hash inconsistencies and
performance problems... therefore Hossa usually runs without this feature at
ICC.
>Does anyone have any information on this for any program?
>
>Thanks,
>
>KarinsDad :)
Best wishes,
Steffen.
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