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Subject: Re: Proposal to Bob and Ricardo! CCT5 - Crafty perspective

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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