Author: Anthony Cozzie
Date: 12:12:41 06/05/04
Go up one level in this thread
On June 05, 2004 at 12:32:47, Will Singleton wrote: >On June 05, 2004 at 10:13:35, Anthony Cozzie wrote: > >>On June 04, 2004 at 19:03:53, Anthony Cozzie wrote: >> >>>From Yace-Zappa >>> >>>[D]3q1rk1/pp1bppbp/3p1npB/8/2rNP1P1/2N2P2/PPPQ4/2KR3R b - - 0 16 >>> >>>1... Nf6xe4 2. f3xe4 Bg7xd4 3. Qd2-d3 b7-b5 4. Nc3-d5 Bd4-e5 5. Bh6xf8 Qd8xf8 6. >>>g4-g5 Qf8-g7 7. c2-c3 Rc4-a4 8. Kc1-b1 Kg8-f8 >>> = (0.32) Depth: 15/38 00:06:02.03 263847kN >>> >>>The game continued Nxe4 Qe3 Rxc3 bxc3 Qh6 Nf6 and now your program should be >>>able to see g5! and white is able to win the queen. >>> >>>Anyone out there that can avoid Nxe4 in reasonable time? >>> >>>anthony >> >>OK, as has been pointed out by about 25 people, the mistake is not Nxe4, but >>Bxh6 (a move which somehow I conviently omitted from the my line). >> >>[D]3q1rk1/pp1bppbp/3p2pB/8/3Nn1P1/2P1QP2/P1P5/2KR3R b - - 0 18 >> >>Even this one is pretty hard for Zappa, it needs 70 seconds to realize Bxh6 is >>losing and 6 minutes switch to Nf6. >> >>1... Bg7xh6 2. Rh1xh6 Ne4-f6 3. Rd1-h1 e7-e5 4. Nd4-f5 Bd7xf5 5. g4xf5 Qd8-a5 6. >>Qe3-g5 Qa5-a3 7. Kc1-d1 Kg8-g7 8. f5xg6 f7xg6 >> = (0.50) Depth: 14/31 00:00:46.41 37517kN >>1 ...Bg7xh6-- >> - (0.25) Depth: 15/30 00:01:08.74 55010kN >>1... Bg7xh6 2. Qe3xh6 Ne4-f6 3. g4-g5 Nf6-h5 4. Rh1xh5 g6xh5 5. Rd1-h1 Qd8-a5 6. >>Rh1xh5 Bd7-f5 7. Nd4xf5 Qa5xf5 8. g5-g6 Qf5xg6 9. Rh5-g5 Rf8-c8 10. Rg5xg6 h7xg6 >> = (-2.83) Depth: 15/34 00:03:02.47 147329kN >>1... Ne4-f6 2. Bh6xg7 Kg8xg7 3. Nd4-f5 Bd7xf5 4. g4xf5 Qd8-a5 5. Qe3xe7 Qa5xa2 >>6. Qe7xb7 Qa2-a3 7. Qb7-b2 Qa3-c5 8. f5xg6 f7xg6 9. Rh1-e1 Rf8-c8 10. Re1-e7 >>Kg7-h6 >> = (0.18) Depth: 15/36 00:05:34.28 269390kN >> >>anthony > > >The time it takes to find Nf6 after seeing the problem with Bxh6 is rather long >for some programs. For example, Crafty (3 min), Ruffian (1:30) and Zappa >(2:30). This is because the problem occurs at a high search depth. > >Amateur does better in switching to the right move, taking only 10 sec. It does >this by "cheating," which is to say, reducing the search depth when a large >score drop occurs. I don't really see a downside to this. > >Crafty >14 191 11683 124623699 1. ... Bxh6 2. Qxh6 Nf6 >14 16 30945 341466474 1. ... Nf6 2. Bxg7 Kxg7 > >Ruffian >14 -161 10004 121228508 Bxh6 Qxh6 Nf6 >14 -5 18402 223090636 Nf6 Bxg7 Kxg7 > >Amateur >16 -243 12517 49364251 Bxh6 Qxh6 Nf6 >13 -243 12517 49364252 Bxh6 >13 87 13581 53146356 Nf6 Bxg7 Kxg7 Well, Zappa's move ordering is *horrible* here. The only problem I see with reducing depth is that you could possibly enter a loop. It definitely is a problem; I like the idea of doing a bit of iterative deepening more than reducing depth at the root though. I also think I'm going to go to automatically failing low if the first move fails low. anthony
This page took 0 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.