Author: Rolf Tueschen
Date: 14:19:53 01/21/03
Go up one level in this thread
On January 21, 2003 at 16:16:19, Robert Hyatt wrote: >On January 21, 2003 at 15:25:21, Rolf Tueschen wrote: > >>On January 21, 2003 at 14:35:50, Robert Hyatt wrote: >> >>>On January 21, 2003 at 09:17:36, Rolf Tueschen wrote: >>> >>>>On January 21, 2003 at 09:09:49, Ricardo Gibert wrote: >>>> >>>>>On January 21, 2003 at 08:52:02, Rolf Tueschen wrote: >>>>> >>>>>>On January 20, 2003 at 23:00:55, Ricardo Gibert wrote: >>>>>> >>>>>>>On January 20, 2003 at 21:57:38, Robert Hyatt wrote: >>>>>>> >>>>>>>>On January 20, 2003 at 21:32:22, Ricardo Gibert wrote: >>>>>>>> >>>>>>>>>On January 20, 2003 at 20:44:21, Robert Hyatt wrote: >>>>>>>>> >>>>>>> >>>>>>>[snip] >>>>>>> >>>>>>>>>>Round 6 Crafty vs Searcher >>>>>>>>>> >>>>>>>>>>A near disaster for the first game of the second day. The same d4 opening >>>>>>>>>>led to a similar position, but things did not go very well here. First score >>>>>>>>>>out of book was -.42, which was typical for every 1. d4 game crafty played as >>>>>>>>>>white. But it was able to pull that up quickly normally. 10 moves out of book, >>>>>>>>>>the score hadn't changed, showing that searcher was playing very well and with >>>>>>>>>>a reasonable amount of understanding of the position. >>>>>>>>>> >>>>>>>>>>Finally by move 24, Crafty was back to a slightly + score, and this held until >>>>>>>>>>it started dropping as it misjudged the queen/rook attacking in the center. At >>>>>>>>>>move 32, the score was -.68 after 16 plies. at move 35, the score was -1.5, at >>>>>>>>>>move 40 -2.0, -2.5 at move 50, -3 at move 60, and at this point Crafty dug >>>>>>>>>>in its heels and pulled the score back to -2.3 where it stayed for a long >>>>>>>>>>while. But it slowly traded pawns, and the score started swinting back. By >>>>>>>>>>move 80, it was -2.0 again, -1.5 by move 85, -1.0 by move 95, and it finally >>>>>>>>>>reported a draw score at move 102. Of all the games it played, this was a >>>>>>>>>>really nice effort as it showed a lot of understanding about king rook and pawn >>>>>>>>>>endings, something I have worked on a lot over the years. >>>>>>>>> >>>>>>>>> >>>>>>>>>I find your last sentence surprising. Crafty was very lucky in this game that >>>>>>>>>Searcherx did not play 62...Re8 62.Kxg3 Rb8 winning easily. >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>>Crafty says if you play Re8 it just plays Rb7 immediately, not Kg3. >>>>>>>> >>>>>>>>Score doesn't change much... >>>>>>>> >>>>>>>>It may be overlooking something, but it isn't going to let black get >>>>>>>>the rook behind the pawn... >>>>>>>> >>>>>>>>Maybe we are at the wrong move? IE you have two move 62's above. >>>>>>>>Do you mean 61. Re8? >>>>>>> >>>>>>> >>>>>>>Yes. 61...Re8 62.Kxg3 Rb8 was my intention. >>>>>>> >>>>>>> >>>>>>>> >>>>>>>>Going back to move 61, and playing Re8 Kg3 Rb8 I get Rd4 and Rb4. White >>>>>>>>loses one of the pawns on the h file, but only one. It isn't clear to me, >>>>>>>>without a lot of study, how black makes progress. The pawn is blockaded, so >>>>>>>>the black rook is stuck on the b file unless it gives check. The black >>>>>>>>king can't abandon the kingside or white will eat the g pawn and the hpawn >>>>>>>>should be enough to force the trade of the rook and a draw... >>>>>>> >>>>>>>[D]8/1p1R2pk/5p2/7P/7P/5Kn1/4r3/8 b - - 0 60 >>>>>>> >>>>>>>61...Re8 62.Kxg3 Rb8 63.Rd4 b5 64.Rb4 Kh6 65.Kg4 Rb7 66.Kh3 Kxh5 67.Kg3 g6 >>>>>>>68.Kh3 f5 69.Kg3 Rb6 70.Kh3 Rc6 71.Rb3 Rc4 is a prosaic and convincing win. >>>>>> >>>>>>A comparable position is available with many different continuations. One is >>>>>>your 61-Re8 others I pointed out in >>>>>>http://www.talkchess.com/forums/1/message.html?278466 >>>>>>The point is that you always winn with the f/g free pawns if they are so good >>>>>>combined. No need to know the rule of the R behind the pawns because you give >>>>>>the b pawn away. >>>>>> >>>>>>Kind regards, >>>>>>Rolf Tueschen >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>>Even though it is later given away, it handcuffs the defense giving time to make >>>>>preparations before giving up the b-pawn to win on the K-side, so it is still an >>>>>important tool. >>>> >>>>No doubt about it. But I was looking for the programmers and you said yourself >>>>that this is difficult to program. So I had a look at totally normal chess, >>>>calculable or countable if you like. And this position with the combined pawns >>>>is won and that is the whole thing. I meant the argument of the "difficult" >>>>Re8-b8 is even not necessary. >>>> >>>>Rolf Tueschen >>>> >>>> >>> >>>One of the problems here is that the f and g pawns are _not_ passed. The f pawn >>>is. The >>>g-pawn is not, because white hangs on to the h-pawn. Here are the problems I >>>see that have >>>to be solved: >>> >>>1. black's rook is behind the b-pawn. If black moves the rook without giving >>>check, the >>>pawn goes away as it is attacked by white's rook. >>> >>>2. I will assume the h5 pawn is going to "go". After Re8 Kxg3 Rb8 Rd4 b5 Rb4 >>>the rooks >>>are stuck. Black can move to b8/b7/b6. White can't move the rook or the pawn >>>advances. >>> >>>3. After black takes on h5 and white keeps the king at g3-h3 to hold the >>>h-pawn, black has >>>a couple of plans. But not all work. The king can't go help the rook, because >>>white's king makes >>>that a long path and it is close to the kingside pawns. the king can't win the >>>white h-pawn by >>>itself, and it can't get the rook up to attack it. So either the king goes to >>>the queenside to help >>>the b-pawn advance, or black tries advancing the f-pawn. >>> >>>White definitely has many problems here, but the question is "are they _all_ >>>unsolvable?" >>>It isn't that clear to me. One thing is for sure, it isn't an "easy win". It >>>is going to take a lot >>>of sweat and calculation. >> >>Sorry, Bob, you must have been tricked by your own program because GR is right, >>this is really easy. Just play through his variation. You as White have no >>chance to deviate from that line more or less. The plan of Black is so easy: >>Your R is on b4, then he puts his R on b6 and when it suits him he will go for >>the double attack on your last pawn h4. So the b pawn has no meaning after all. >>It is just to keep you in tension with your R. Then, when the last pawn of White >>has been taken, the rest is known theory. And you can't do anything against it. >>So - what I found very clever during the game, that Crafty played merry-go-round >>in the center with R and N and for all neutralized the dangerous d pawn, that >>does not draw because of the given final. And Black could win earlier, with my >>move Rf2 instead Rc3, and your K is outplaced. So you must search for >>alternatives way earlier. The structure with the double pawn is weak. First the >>d pawn and then Black also had the free b pawn afterwards, so basically it's not >>the good game by Crafty as I had thought at first. But overall you were very >>good with Ferret who normally should draw in the last round and then tie with >>you. Ferret played really sharp chess while you are extremely good in your time >>management, that was very obvious to me. Was one of the best results for you, >>right? >> >>Rolf Tueschen >> >> >> > >No. The ferret result was _bad_. A loss is bad. :) > >the ruffian and yace games were good. They were wins. :) > >However, until I have time to study the searcher endgame, I can't say much more. >It isn't an "easy" win in my opinion (by black). It might be winnable. But >there >are enough places to go wrong that a human might well have problems. IE it >would be interesting to play this against a human at a minute a move or whatever >to see how "easy" it turns out to be. :) > >I would expect more than one "oh shit!" during the experiment. :) > >Humans might think that they know all about rook endings. But if you go back >prior >to endgame tables, humans thought they knew all about KQ vs KR, until belle >showed >the world that the king and rook to _not_ stay together for best defense. > >So while I don't like white's position, until I study it in detail, I haven't >concluded it >is lost yet, myself... PROPOSAL: As Ricardo said he is now sure how to win against all defense. Bob, couldn't we organize that on ICC on a specific date so that many of us could follow? Ricardo, would that be possibl for you to go on ICC? Rolf Tueschen > > >>>>> >>>>>[snip]
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