Author: Vincent Diepeveen
Date: 19:20:43 12/07/99
Go up one level in this thread
On December 07, 1999 at 14:36:50, Robert Hyatt wrote:
>On December 07, 1999 at 09:17:07, Vincent Diepeveen wrote:
>
>>On December 06, 1999 at 08:46:09, Robert Hyatt wrote:
>>
>>>On December 06, 1999 at 02:54:30, Harald Faber wrote:
>>>
>>>>On December 05, 1999 at 22:35:23, Michael Fuhrmann wrote:
>>>>
>>>>>Bob Hyatt stated in a recent post that all chess programs have "absolutely
>>>>>glaring holes." What are the specific weaknesses of some of the top programs.
>>>>
>>>>In most cases it is their own king safety.
>>>
>>>
>>>That is certainly a big one.
>>
>>should specify by program though. not all
>>gms are the same, not all programs are the same.
>>
>>>Another is over-rating the attacking chances relative to the opponent's
>>>king safety. IE many programs think that after Bxg3 hxg3 that white's
>>>king is very unsafe, when in reality, it is not with a doubled pawn at
>>>g3.
>>
>>Right, this problem is extreme by
>>the following programs/systems:
>> - deep thought
>> - deep blue
>> - deepviolet (at the iccserver, softwareversion PII-400 getting 22k nps)
>>
>>Not even gnuchess is having the f2g2g3 pattern detection as bad implemented
>>as the above 3.
>>
>>>Passed pawns. Many over-value these, to the point that they will create an
>>>advanced one that becomes lost laster. Others have no clue about the advantage
>>
>>Yes crafty even says 2 pawns at the third row are worth a rook
>>not taking into account the king.
>
>You may not be able to read a bitmap program properly. Two connected passers
>on the 6th are _not_ worth a rook, _unless_ the king is far enough away that
>it can't reach either promoting square. And neither of the pawns can be
>blockaded...
Wrong, white to move all pawns on 3d rank, so if we only make Rb7 here then
all pawns are inside quadrant of white king or can be stopped by rook.
just the BIG luck here for black is that there is a pawn on e3, otherwise
ke3 wins here for black bigtime.
Black(1): white
White(1): d
+---+---+---+---+---+---+---+---+
8 | | | | | | | | |
+---+---+---+---+---+---+---+---+
7 | | | | | | | | *P|
+---+---+---+---+---+---+---+---+
6 | | | | | | *K| | |
+---+---+---+---+---+---+---+---+
5 | | | | | | *P| | |
+---+---+---+---+---+---+---+---+
4 | *P| | | | | P | | |
+---+---+---+---+---+---+---+---+
3 | P | | *P| *P| P | K | | |
+---+---+---+---+---+---+---+---+
2 | | | | | | | | P |
+---+---+---+---+---+---+---+---+
1 | | R | | | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
White(1): anal
Analyze Mode: type "exit" to terminate.
end-game phase
clearing hash tables
time surplus 0.00 time limit 30.00 (3:00)
s depth time score variation (1)
1 0.00 -2.49 1. Rb7
1-> 0.03 -2.49 1. Rb7
2 0.06 -- 1. Rb7
2 0.08 -2.97 1. Rb7 h5
2 0.11 -2.44 1. Rb6+ Kf7 2. Rb7+ Kg6
2 0.14 ++ 1. e4!!
2 0.17 -1.79 1. e4 h5 2. exf5
2 0.20 0.92 1. Rd1 c2 2. Rc1
2 0.22 0.93 1. Rc1 d2 2. Rd1
2-> 0.26 0.93 1. Rc1 d2 2. Rd1
3 0.28 -- 1. Rc1
3 0.31 -2.91 1. Rc1 d2 2. Rd1 c2 3. Rxd2 c1=Q
3 0.34 -2.13 1. Rb6+ Ke7 2. Rb7+ Kd6 3. Rxh7
3 0.37 -1.56 1. e4 fxe4+ 2. Ke3 Kf5
3-> 0.41 -1.56 1. e4 fxe4+ 2. Ke3 Kf5
4 0.47 -- 1. e4
4 0.52 -2.04 1. e4 c2 2. e5+ Ke6 3. Rb6+ Ke7 4.
Rd6
4 0.58 ++ 1. Rb6+!!
4-> 0.65 -1.17 1. Rb6+
5 0.72 -- 1. Rb6+
5 0.89 -2.23 1. Rb6+ Ke7 2. Rb7+ Kd8 3. Rxh7 c2
4. Rh8+ Kd7 5. Rc8
5-> 1.20 -2.23 1. Rb6+ Ke7 2. Rb7+ Kd8 3. Rxh7 c2
4. Rh8+ Kd7 5. Rc8
6 1.78 -2.03 1. Rb6+ Ke7 2. Rb7+ Kd6 3. Ra7 c2 4.
Rxa4 Ke6 5. Rd4
6 1.97 -1.94 1. e4 c2 2. e5+ Ke7 3. Rb7+ Kd8 4.
Rb6 Kc7 5. Rd6
6-> 2.24 -1.94 1. e4 c2 2. e5+ Ke7 3. Rb7+ Kd8 4.
Rb6 Kc7 5. Rd6
7 2.64 -1.93 1. e4 c2 2. e5+ Ke7 3. Rb7+ Ke6 4.
Rb6+ <HT>
7-> 3.36 -1.93 1. e4 c2 2. e5+ Ke7 3. Rb7+ Ke6 4.
Rb6+ <HT>
8 4.35 -2.09 1. e4 c2 2. e5+ Ke7 3. Rb7+ Kd8 4.
Rb6 c1=Q 5. Rd6+ Ke7 6. Rxd3 Ke6
8 5.69 -1.74 1. Rb6+ Ke7 2. Rb7+ Ke6 3. Rb6+ Kf7
4. Rb7+ Ke8 5. Rxh7 c2 6. Rc7 d2 7.
Rc8+ Ke7 8. Rxc2 d1=Q+
8-> 6.50 -1.74 1. Rb6+ Ke7 2. Rb7+ Ke6 3. Rb6+ Kf7
4. Rb7+ Ke8 5. Rxh7 c2 6. Rc7 d2 7.
Rc8+ Ke7 8. Rxc2 d1=Q+
crafty is so happy to play Rxb2 because it finds a position with
king in quadrant winning for black though it's a rook down!
So that's 8 pawns if i'm not mistaken. 4 pawns bonus each pawn
So WITHOUT the pawn on e3 it might at 1 ply be very happy here with
white?
SURE!!!!!
-0.76 even though it's a full rook down!
White(1): d
+---+---+---+---+---+---+---+---+
8 | | | | | | | | |
+---+---+---+---+---+---+---+---+
7 | | | | | | | | *P|
+---+---+---+---+---+---+---+---+
6 | | | | | | *K| | |
+---+---+---+---+---+---+---+---+
5 | | | | | | *P| | |
+---+---+---+---+---+---+---+---+
4 | *P| | | | | P | | |
+---+---+---+---+---+---+---+---+
3 | P | | *P| *P| | K | | |
+---+---+---+---+---+---+---+---+
2 | | | | | | | | P |
+---+---+---+---+---+---+---+---+
1 | | R | | | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
White(1): an
Analyze Mode: type "exit" to terminate.
end-game phase
clearing hash tables
time surplus 0.00 time limit 30.00 (3:00) [easy move]
s depth time score variation (1)
1 0.00 -0.76 1. Ke3
1-> 0.06 -0.76 1. Ke3
2 0.08 ++ 1. Ke3!!
2 0.11 0.00 1. Ke3 c2 2. Rc1
2-> 0.14 0.00 1. Ke3 c2 2. Rc1
3 0.17 -0.32 1. Ke3 d2 2. Rd1 c2 3. Kxd2 cxd1=Q+
4. Kxd1
3-> 0.24 -0.32 1. Ke3 d2 2. Rd1 c2 3. Kxd2 cxd1=Q+
4. Kxd1
4 0.30 ++ 1. Ke3!!
4 0.33 2.85 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3
4-> 0.40 2.85 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3
5 0.44 ++ 1. Ke3!!
5 0.50 4.87 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3 h5 4.
Kxd2
5-> 0.66 4.87 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3 h5 4.
Kxd2
6 0.80 4.78 1. Ke3 Ke6 2. Kxd3 Kd5 3. Kxc3 Ke4
6-> 1.10 4.78 1. Ke3 Ke6 2. Kxd3 Kd5 3. Kxc3 Ke4
7 1.53 4.78 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3 Kd5 4.
Kxd2 Ke4
7-> 2.07 4.78 1. Ke3 d2 2. Kd3 Ke6 3. Kxc3 Kd5 4.
Kxd2 Ke4
quit 8 2.12 1/20 1. Ke3
White(1): quit
execution complete.
K:\chess\crafty>
So now the ultimate test: let's get away the e3 pawn at position 2
of the WAC test. Taking on b2 is now simply losing a rook. Does crafty
consider this?
SURE!!!!
Black(1): d
+---+---+---+---+---+---+---+---+
8 | | | | | | | | |
+---+---+---+---+---+---+---+---+
7 | | | | | | | | *P|
+---+---+---+---+---+---+---+---+
6 | | | | | | *K| | |
+---+---+---+---+---+---+---+---+
5 | | | | | | *P| | |
+---+---+---+---+---+---+---+---+
4 | *P| | *P| | | P | | |
+---+---+---+---+---+---+---+---+
3 | P | *R| | *P| | K | | |
+---+---+---+---+---+---+---+---+
2 | | P | | R | | | | P |
+---+---+---+---+---+---+---+---+
1 | | | | | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
Black(1): anal
Analyze Mode: type "exit" to terminate.
end-game phase
clearing hash tables
time surplus 0.00 time limit 30.00 (3:00)
s depth time score variation (1)
1 0.00 2.28 1. ... Ke6
1-> 0.03 2.28 1. ... Ke6
2 0.06 2.18 1. ... Ke6 2. Ke3
2-> 0.09 2.18 1. ... Ke6 2. Ke3
3 0.12 2.28 1. ... Ke6 2. Ke3 Kd5
3 0.15 ++ 1. ... Rxb2!!
3 0.17 3.81 1. ... Rxb2 2. Rxb2 c3
3-> 0.21 3.81 1. ... Rxb2 2. Rxb2 c3
4 0.23 -- 1. ... Rxb2
4 0.26 3.44 1. ... Rxb2 2. Rxb2 c3 3. Rd2 cxd2
4-> 0.29 3.44 1. ... Rxb2 2. Rxb2 c3 3. Rd2 cxd2
5 0.32 -- 1. ... Rxb2
5 0.35 0.71 1. ... Rxb2 2. Rxb2 c3 3. Rb6+ Ke7
4. Ke3
>
>
>
>
>>
>>Patzer seems giving a pawn at the 6th rank +3.0 or something anyway.
>>
>>Nimzo is very happy too with passed pawns.
>>
>>Basically it's tough to detect how well pawns are stopped, i bet all programs
>>have to some extend big problems with this as the evaluation is so dependant
>>upon just a few terms here. Every term is having a big impact on the evaluation
>>of the position.
>>
>>>of an outside (or distant) passed pawn. An ancillary point here is that even
>>>if a program recognizes a passed pawn as good (outside passed pawn) many don't
>>>recognize a 'distant majority' which is essentially the same thing. I have
>>>seen more than one program trade into a K+P vs K+P (multiple p's on both
>>>sides) ending that was dead lost, even though they might have been a pawn
>>>up or have a more advanced passer.
>>
>>Right, this might be a problem that will remain long time a problem.
>>there are many factors and reevaluations
>>to consider before you can apply to such a far
>>majority a winning bonus.
>>
>>>Some value a rook on the 7th too highly, particularly after all the pawns have
>>>advanced and the king is centralized. A rook on the 7th there isn't doing
>>>anything, yet more than one program is very happy with it.
>>
>>a problem in diep is it wants to centralize king in endgame always.
>>usual that's good but sometimes...
>>
>>>Some (including older versions of crafty) value connected passed pawns more
>>>valuable than two isolated passed pawns... This is wrong in king and pawn (only)
>>>endings...
>>>
>>>The list goes on and on...
>>
>>Right, however the biggest problem are closed positions.
>>The problem with closed positions is that the rules are sometimes the
>>opposite of normal positions.
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