Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: developing Junior (and other pro programs)

Author: Uri Blass

Date: 01:00:57 08/31/02

Go up one level in this thread


On August 31, 2002 at 03:26:01, Dave Gomboc wrote:

>>This is exactly the case for Junior and Fritz and they simply do not care about
>>small improvement that they can get.
>
>That, I don't believe.
>
>>They know that there are positions when the program cannot see simple tactics
>>but they do not care to fix it.
>>
>>There are positions when Junior cannot see simple tactics and Amir ban knows
>>about it but he did not fix it at least not in Junior7(some years after he got
>>the information).
>
>That's probably because it would hurt the program overall.  I'm sure he does
>what he thinks is best for overall program strength.

I believe that the reason for Junior is that it is not
easy to fix it and be sure that you do not generate
other bugs but I do not think that it is impossible
to do it.

I believe that in most cases
professional do not work harder than the amaturs.

>
>>There are positions when Fritz cannot see simple mate because of null move
>>pruning.
>
>I'm sure Frans Morsch is well aware of that too.

Yes but he does nothing to fix it and it does more mistakes than other programs
because of null move pruning.
I see no reason to use null move pruning after the first
move of the pv but this is exactly what Fritz does.

I already posted the analysis when Fritz finds the right move Nc6
that is winning(white is in zunzwang) but the score
drop every iteration because it does not want to analyze a move that threats
nothing.

Here is the relevant position again

[D]1n6/1P6/8/2P5/p3kp1p/6p1/1P4K1/4N3 b - - 0 1

This position can happen in games

Deep Fritz(black) played against Junior7(White).

Junior7 already saw a score of 11.40 against itself when it played 54.c5 but
Deep fritz blundered because of pruning the line that it wanted to play.

I remember from analyzing another study that
this kind of behaviour is in Fritz for years
(Fritz3,Fritz4,Fritz5)
and I wonder why Fritz insist to use null move in
the wrong way(I do not know about Deep Fritz7 and this analysis
is with the first Deep Fritz that came after fritz6)

Here is the game it is taken from copied from Deep Fritz's
Gui(if you look in the line that is not the main line you can see
54.c5 and the horrible blunder that Deep Fritz did in the game).

Luba kristol - Uri blass [B80]
[Blass,U]

 32768kB, F5book.ctg. PentiumIII
 1.e4 c5 2.Nf3 13.11-14.11 2...d6 15.11-15.11 3.d4 16.11-19.11 3...cxd4 4.Nxd4
Nf6 white 4 days black 0 days 5.Nc3 22.11-23.11 5...a6 26.11-26.11 6.f3
29.11-29.11 6...e6 1.12-3.12 7.Be3 5.12-7.12 7...b5 12.12-12.12 8.Qd2
14.12-15.12 8...Nbd7 18.12-18.12 9.g4 21.12-26.12 9...h6 28.12-4.1 10.0-0-0
8.1-10.1 10...Bb7 14.1-16.1 11.Bd3 17.1-18.1 11...Ne5 21.1-26.1 12.Rhe1 31.1-1.2
12...b4 4.2-12.2 13.Nce2 d5 vacation-7.3 14.Ng3 9.3-18.3 14...dxe4 20.3-1.4
15.Bxe4 Nxe4 15.4-16.4 16.Nxe4 17.4-18.4 16...Bxe4 22.4-23.4 17.fxe4
25.4-28.4-1.5 17...Bc5 1.5-2.5 18.Qe2 4.5-8.5 18...Qb6 9.5-13.5 19.Kb1 15.5-17.5
19...0-0 18,5-20.5 20.Rd2 22.5-23.5 20...a5 24.5-29.5  -0.63/17  1:47:34
21.Red1 31.5-1.6 21...Rfd8 [21...Qa6 22.Qxa6 Rxa6 23.Nf5 Rc6 24.Bxc5 Rxc5 25.Ne3
Kh7] 22.h4 Qa6 23.Qxa6  -0.42/18  14:59  Rxa6  -0.72/15  2:37  24.Nxe6 (Nb3)
-0.59/18  8:10  24...Rxd2  -1.06/17  7:35  25.Rxd2  -0.81/19  6:38  Rxe6
-0.97/17  11:32  [25...Be7 26.Nc7  -0.53/19  12:51  Rf6  -0.72/16  8:00  27.Rf2
-0.60/20  29:50  Rc6  -0.81/16  8:39  28.Nd5  -0.83/20  25:21  Bxh4  -0.78/16
12:36  29.Rf5 (Re2)  -0.86/20  26:27  29...Nxg4  -1.06/16  10:24  30.Bb6
-0.89/20  21:14  a4  -1.22/16  20:40  31.Ba5  -0.90/20  29:44  Re6  -1.16/16
16:06  32.Bxb4  -0.88/20  24:11  Rxe4  -1.16/16  18:54  33.a3  -0.92/20  8:56
Be1 (Rd4)  -1.13/15  10:55  34.Kc1 (c3)  -0.71/19  7:53  34...g6  -1.13/16
13:17  35.Rf1  -0.85/20  14:54  Bxb4 (Bh4)  -1.03/16  9:33  36.axb4  -0.60/18
4:04  f5 (Kg7)  -1.03/16  12:07  37.b5  -0.62/20  5:49  Kf7  -1.13/16  11:28
38.Rf4 (b6)  -0.77/20  12:14  38...Rxf4  -1.34/17  6:18  39.Nxf4  -0.80/21  1:55
 Ne5 (Nf6)  -1.41/19  7:12  40.b6  -1.01/23  6:13  Nc6 (Nd7)  -1.47/19  11:28
41.Kd2 (b7)  -0.70/21  7:05  41...h5 (g5)  -1.56/18  10:55  42.Nd3  -0.75/22
10:53  Ke6 (h4)  -1.63/17  8:29  43.Nf4+ (Nc5+)  -0.78/22  10:37  43...Kf6
-1.78/18  6:09  44.Ke1 (b7)  -0.78/21  5:17  44...h4  -2.00/18  4:56  45.Kf2
(Kf1)  -0.89/22  6:56  45...g5  -2.03/18  5:06  46.Nd3  -1.03/21  7:01  f4 (Ke6)
 -2.19/18  6:01  47.Kg1 (b7)  -1.11/21  5:35  47...Kf5  -2.28/19  7:21  48.b7
-1.46/22  4:53  Nb8  -2.44/18  4:32  49.Kf2 (c4)  -1.83/23  3:23  49...g4
-3.75/19  2:24  50.Kg2  -2.12/23  5:35  g3  -3.63/20  3:48  51.c3  -4.98/24
6:47  Ke4  -4.25/20  1:27  52.Ne1  -5.28/23  11:05  Nd7 (Nc6)  -1.94/20  14:33
53.c4  -6.18/24  4:11  Nb8  -0.88/19  3:45  54.c5  -11.40/24  2:56  Ke3 (Nc6)
-0.88/17  3:53  (54...Nc6) 55.Nc2+  -0.68/20  1:02  Kd3  -1.09/19  5:10  56.c6
-0.91/20  1:21  Nxc6  -0.81/18  9:24  57.Nb4+  -0.55/20  5:24  Ke2 (Ke3)
-0.56/18  7:20  58.Nxc6  -0.55/20  5:27  f3+  -0.53/16  4:51  59.Kh3  -0.55/21
16:44  f2  -1.06/15  1:53  60.b8Q  -0.56/19  2:43  f1Q+  -0.75/13  1:15  61.Kxh4
 -0.56/18  1:30  Qf6+ (Qh1+)  0.00/13  2:36  62.Kxg3  -0.56/18  6:05  Qf3+
(Qxc6)  -0.59/13  1:17 ] 26.Bxc5  -0.84/20  7:33  Nxg4  -1.00/16  5:24  27.Kc1
(Rd8+)  -0.89/20  34:55  27...Rxe4  -1.00/16  12:39  28.Rd4 (Bb6)  -0.81/20
43:54  28...Rxd4 (Nf6)  -0.97/17  7:38  29.Bxd4  -0.88/22  5:23  h5 (f6)
-1.19/19  10:42  30.Kd1  -0.70/25  17:29  f6  -1.00/20  11:05  31.Bb6  -0.55/24
8:18  a4  -1.09/20  11:52  32.Bc5  -0.55/25  18:40  g5  -0.97/20  12:24  33.hxg5
 -0.41/24  7:58  fxg5  -0.97/19  6:44  34.Ke2  -0.39/25  10:15  h4 (Kf7)
-1.03/19  10:14  35.Bxb4  -0.35/23  5:20  Kf7  -0.78/19  11:57  36.Bd2 (b3)
-0.26/23  10:07  36...Kg6  -0.97/18  6:31  37.b3 (b4)  -0.26/24  10:31  37...h3
-0.81/20  12:17  38.Kf1  -0.16/22  2:57  axb3  -0.91/17  18:09  39.cxb3
-0.11/23  6:33  Ne5 (Kf5)  -0.47/18  20:55  40.a4  0.00/23  6:19  Nf3  -0.94/19
5:02  41.Ba5  0.00/24  5:51  g4 (Nd4)  -0.16/20  11:29  42.Kf2  0.00/24  4:06
Kf5 (Nd4)  0.12/21  9:13  43.Bc7  -0.06/23  1:36  Nd2 (Ke6)  0.00/21  5:05
44.a5  0.01/25  6:19  Ne4+  0.00/21  8:11  45.Kg1  -0.14/26  14:45  Nc5  0.00/22
 5:19  46.Bd6  0.00/28  8:03  Na6  0.00/23  6:29  47.Bh2 (Kh2)  0.00/29  3:48
47...Kf6 (Ke4)  0.00/23  4:26  48.Kf2  -0.14/26  5:35  Ke6 (Kf5)  0.00/23  5:07
49.Kg3  0.00/29  4:15  Kd7 (Kd5)  0.00/25  3:51  50.Kxg4  0.00/31  5:21  Kc6
0.00/26  5:12  Line


Uri



This page took 0.03 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.