Author: Miguel A. Ballicora
Date: 15:41:14 09/22/01
Go up one level in this thread
On September 22, 2001 at 17:17:26, Robert Hyatt wrote: >On September 22, 2001 at 12:40:57, Miguel A. Ballicora wrote: > >>On September 22, 2001 at 09:57:10, Robert Hyatt wrote: >> >>>On September 22, 2001 at 01:39:15, Miguel A. Ballicora wrote: >>> >>>>On September 22, 2001 at 00:52:06, Robert Hyatt wrote: >>>> >>>>>On September 22, 2001 at 00:43:03, Robert Hyatt wrote: >>>>> >>>>>>On September 21, 2001 at 23:45:54, Miguel A. Ballicora wrote: >>>>>> >>>>>>>On September 21, 2001 at 23:01:29, Robert Hyatt wrote: >>>>>>> >>>>>>>>On September 21, 2001 at 17:01:35, Miguel A. Ballicora wrote: >>>>>>>> >>>>>>>>>On September 21, 2001 at 16:45:44, Robert Hyatt wrote: >>>>>>>>> >>>>>>>>>>On September 21, 2001 at 16:27:01, Gian-Carlo Pascutto wrote: >>>>>>>>>> >>>>>>>>>>>On September 21, 2001 at 14:57:20, Robert Hyatt wrote: >>>>>>>>>>> >>>>>>>>>>>>I don't mind that kind of mis-evaluation so much. If anybody wins, white >>>>>>>>>>>>wins. What I would not like is to see that kind of evaluation and then lose >>>>>>>>>>>>the game... >>>>>>>>>>> >>>>>>>>>>>The problem is when crafty prefers the 1.8 from this ending over the 1.7 from >>>>>>>>>>>another ending that _is_ won for white. >>>>>>>>>>> >>>>>>>>>>>That'll cost you half a point. >>>>>>>>>>> >>>>>>>>>>>-- >>>>>>>>>>>GCP >>>>>>>>>> >>>>>>>>>> >>>>>>>>>>I don't disagree. But it is just as important to not lose when you can win >>>>>>>>>>or draw. The not drawing when you can win is another level of tuning. I need >>>>>>>>>>to study the ending because a pawn on the a and c file becomes very hard for >>>>>>>>>>a lone king to stop... it might have simply made a mistake and drawn a won >>>>>>>>>>position in this case.. I didn't look at it very carefully (yet). >>>>>>>>> >>>>>>>>>It looks drawn. As you already know, the advantage of the outside passer is that >>>>>>>>>you can sacrifice it and the king can go and eat up the opponent pawns on the >>>>>>>>>other side. In this case it is impossible (that's the problem here). For >>>>>>>>>instance, place the pawns in g6,h5,g4. How can the white king capture them? it >>>>>>>>>can't because as soon as you capture g6 black plays h4 and promotes. On the >>>>>>>>>other hand, two passers cannot beat a king on the Q side, they need the help of >>>>>>>>>the wKing. however, the wK cannot go to the Q side because black promotes. >>>>>>>>> >>>>>>>>>Regards, >>>>>>>>>Miguel >>>>>>>> >>>>>>>> >>>>>>>>I don't believe it is quite that simple. If the pawns are zugged on the >>>>>>>>kingside, the two passers on the queenside can easily win. This is the >>>>>>>>attraction of "wild 7" on ICC, which is what the "mini game" is all about. >>>>>>> >>>>>>>I am not sure what you mean by zugged pawns. Anyway, white cannot capture the >>>>>>>pawns in any case, so how can white win? two passers, if they are not separated >>>>>>>enough, cannot win without king support. >>>>>>>The only chance is a race, when white king rush to the Q side to support them >>>>>>>letting a black pawn to promote. >>>>>>> >>>>>>> >>>>>>>>In this zug-less position (at present) things aren't so clear, of course, >>>>>>>>but >>>>>>>>put the black pawns at g5 and h6 and the white pawn at g4, and this turns >>>>>>>>into a simple white win... >>>>>>> >>>>>>>Black plays h5 and it is a draw. I think I did not understand. >>>>>>> >>>>>>>Regards, >>>>>>>Miguel >>>>>> >>>>>> >>>>>>You are assuming that a KQ vs KQPP is a draw? IE after h5, I play gxh5 and I >>>>>>promote first. >>>> >>>>But I play g6xh5 first and you don't promote ;-) >>>>I think we are talking about different things. You are setting a position >>>>with only h6 and g5? then I have pawn less and has little to do with the game >>>>itself. >>>> >>> >>> >>>OK... let's back up a bit. >>> >>>I have an a and c pawn, and a pawn at g5. You have pawns at g6/h7. That is >>>the position in the game under discussion. Crafty was up a pawn, and had an >>>eval of +2.something, although the game was later drawn. >>> >>>I am going to use my king to advance my a/c pawns. If you leave that >>>area, I will promote easily. If you play h6, I am going to play gh and >>>promote on the h file if your king isn't close enough, or on the a file if >>>you try to stop the h pawn. >> >>This position has nothing to do with the game. I believe you are trying >>to make a point, but I do not see it. >> > > >The position is related to the game because of the following: > >White has three pawns, black has two. White has the passed a and c pawns, >but black's pawns are immobilized. > >I don't think it is easy to evaluate this game as won, lost or drawn, just >by looking at material, or anything else. It is very complex... > > >>>That was the reason for setting up the kingside pawns so that you don't have >>>any moves over there. With my queen-side pawns at (say) c4/a4 I don't see how >>>your king is going to stop them. Wheneven you approach one, the other advances. >>>If you "wait" I wait also by advancing my king. >> >>You can never promote with a and c pawns without king support unless they find >>a way to reach the 6th rank safely. Even if you can wait with your king. If you >>cannot wait with your king is even worse, you lose. (in fact, you even lose with >>three pawns a, b and c). >> >>[D]8/8/1k6/8/P1P5/7P/6Pp/6K1 w - - >> >>this is a draw. Even with the bKing in b7 or b8. >> >>Regards, >>Miguel > >Not quite. Because the black king can't abandon the two white pawns. Nor >can it attack them. So the black king is fixed. If the white king gets to >the black pawns quickly enough, white wins easily. That was the problem with >this position, from crafty's perspective... > > > > >> >>>This was why I said it doesn't seem so easy to try to statically evaluate >>>this, although I think I have some ideas of how to do this a bit more >>>accurately by fixing what looks like a bug.
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