Author: John Merlino
Date: 17:25:20 06/05/00
Go up one level in this thread
On June 05, 2000 at 17:51:35, blass uri wrote: >On June 05, 2000 at 11:46:41, Robert Hyatt wrote: > >>On June 05, 2000 at 10:31:32, blass uri wrote: >> >>>On June 05, 2000 at 09:09:51, Robert Hyatt wrote: >>> >>>>On June 05, 2000 at 08:22:44, Steffen Jakob wrote: >>>> >>>>>Hi! >>>>> >>>>>This is a position from an interesting standard game MissSilicon - Hossa, played >>>>>today at ICC: >>>>> >>>>>[D]5k2/7K/6P1/1p3p2/1P5P/1Pb5/8/8 w >>>> >>>> >>>> >>>>I think there are times where you have to depend on your search. Normally >>>>this is won by black, because black has a bishop to stop white's pawns. I >>>>suspect that if you try to write special-purpose code to catch this, it will >>>>end up being wrong more than it is right. >>> >>>I agree that writing a special code to catch this case and many other cases is >>>not trivial but I believe that it is not impossible. >>> >>> This is a precise tempo-counting >>>>issue that just barely lets the 'loser' win. >>>> >>>>I'd likely just take the loss and run. It takes Crafty 9 plies (0 seconds >>>>of course) to see that the bishop is not winning. I don't see an obvious >>>>evaluation trick to make this show up faster... >>> >>>Hiarcs7.32 needs only 5 plies to see that white is winning because of >>>extensions. >>> >>>Uri >> >> >>That doesn't matter. How _long_ does Hiarcs need? It doesn't matter whether >>you need 5 plies or 9 plies. What matters is "how many seconds"??? Because it >>is easy to extend a lot and pick this up quicker (shallower plies) but take >>longer overall to find the problem. Here is what I get, for reference: >> >> nss depth time score variation (1) >>starting thread 1 >>starting thread 2 >>starting thread 3 >> 1 0.00 -5.90 1. h5 >> 1-> 0.00 -5.90 1. h56 >> 2 0.00 -- 1. h5 >> 2 0.00 -6.77 1. h5 Bxb4 >> 2 0.00 -6.52 1. Kh6 f4 >> 2-> 0.01 -6.52 1. Kh6 f4 >> 3 0.01 -6.22 1. Kh6 f4 2. h5 >> 3 0.01 ++ 1. h5!! >> 3 0.01 -5.40 1. h5 Bg7 2. h6 >> 3-> 0.01 -5.40 1. h5 Bg7 2. h6 >> 4 0.02 -5.14 1. h5 f4 2. h6 Bxb4 >> 4-> 0.02 -5.14 1. h5 f4 2. h6 Bxb4 >> 5 0.23 ++ 1. h5!! >> 5 0.24 -3.95 1. h5 f4 2. h6 f3 3. g7+ Bxg7 4. hxg7+ >> 5-> 0.24 -3.95 1. h5 f4 2. h6 f3 3. g7+ Bxg7 4. hxg7+ >> 6 0.25 -4.26 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 >> 6-> 0.26 -4.26 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 >> 7 0.27 -4.26 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 4. >> Kh7 >> 7-> 0.27 -4.26 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 4. >> Kh7 >> 8 0.28 -4.43 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 4. >> g7+ Kg8 5. Kg5 >> 8-> 0.29 -4.43 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 f4 4. >> g7+ Kg8 5. Kg5 >> 9 0.38 ++ 1. h5!! >> 9 0.49 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 Kg7 5. Kxf5 >> 9-> 0.49 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 Kg7 5. Kxf5 >> 10 0.50 3.68 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kg7 >> 10-> 0.51 3.68 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kg7 >> 11 0.52 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kg7 6. Kf5 >> 11-> 0.53 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kg7 6. Kf5 >> 12 0.55 3.88 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kh8 6. Ke5 Kg7 >> (2) 12-> 0.58 3.88 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kh8 6. Ke5 Kg7 >> 13 0.60 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kh8 6. Ke5 Kg7 7. Kf5 >> (2) 13-> 0.63 3.78 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kh8 6. Ke5 Kg7 7. Kf5 >> 14 0.66 ++ 1. h5!! >> 14 6.49 4.19 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kf8 6. Kg5 Ke7 7. g7 >> Kf7 8. Kh6 >> 14-> 6.56 4.19 1. h5 Bg7 2. h6 Bxh6 3. Kxh6 Kg8 4. >> Kg5 f4 5. Kxf4 Kf8 6. Kg5 Ke7 7. g7 >> Kf7 8. Kh6 >> >> >>Crafty finds the right move from depth=1. After .38 seconds it realizes that >>white is winning. I can crank up the passed pawn extension and see this >>quicker in terms of depth, but the time will probably be slower overall. IE >>don't be mislead by 'shallow depth finding'. I think depth doesn't matter at >>all. It is _time_. > >I do not know the exact time but it needs clearly less than 1 second on p200MMX >to see evaluation of +4.88 > >Uri Chessmaster 7000 is the same, needing less than 1 second to find the move with a score of +4.44 at a depth of 9/10. 1.h5 Bg7 2.h6 Bxh6 3.Kxh6 Kg8 4.Kg5 Kf8 5.Kxf5 -- the same line that Crafty finds. So the results are pretty much the same. The score jumps dramatically to +8.43 at depth 12/13 after 13 seconds. 5... Kg8 6.Ke6 Kg7 7.Kd7 Kxg6 8.Kc6 Kf5 9.Kxb5 jm
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