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

Author: Christophe Theron

Date: 19:06:52 08/31/02

Go up one level in this thread


On August 31, 2002 at 21:11:43, Vincent Diepeveen wrote:

>On August 31, 2002 at 04:00:57, Uri Blass wrote:
>
>>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.
>
>they will be happy with such statements...
>
>Most obviously won't be able to answer that because they don't like
>to work and prefer to stay on the beach instead :)


Hey, I'm reading this, you know! ;-)

It's not for the beach. It's for the girls. ;-)





>>>>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.
>
>any fritz7 comments instead of only the completely outdated deepfritz?
>of course i tried fritz7 and it also fails miserably.
>
>Obviously you need to use nullmove first move after pv always
>when you don't use alphabeta, but MTD instead.


That's a clever observation.

So you think Fritz is using MTD(f)?




     Christophe





>>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



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