< Earlier Kibitzing · PAGE 4 OF 4 ·
|Mar-13-07|| ||fm avari viraf: To be candid, I didn't like Spassky's position. In fact, Ribli could have grind his advantage into a win. But Spassky being a magician tactician found a resourceful move Qxh6+ & salvaged half a point.|
|Mar-13-07|| ||maxfrank: Actually, the game seemed resignable at move 81. Perhaps that was Spassky's intention. I'd guess, "I've hung on so far. I'll play on a little with the time control adrenaline still affecting Ribli, and (84 Kh4) - oops! he just screwed up!!!"|
|Mar-13-07|| ||mig55: I think ....Qd2+ draws too?|
|Mar-13-07|| ||euripides: <max> for more on why the general principles in Fine/Benko are not to be trusted, see http://www.jeremysilman.com/book_re...|
|Mar-13-07|| ||euripides: <max> thanks for the von Trier suggestion - I have seen the old Pasolini version many years ago, but not this - I will keep an eye out.|
|Mar-13-07|| ||Sneaky: Even if there are other ways to draw this position according to tablebase, there's no doubt about which move is the best move. For today, you either saw ...Qxh6+ or you get no credit, in my opinion.|
I saw it quickly only because it was Tuesday. If they gave me this on Friday I probably would give up without even trying, thinking it must be over my head!
|Mar-13-07|| ||Dr.Lecter: Well, I thought there might be a perpetual, but couldn't find any. Conclusion: it took me over 10 seconds to find the answer.|
|Mar-13-07|| ||cionics: I feel really dense, but can someone help a neophyte! What happens after 86 Kxh6? I don't see why this is a draw. Shouldn't white be able to promote the pawn eventually? Also, what is the meaning of a "tablebase draw". Thanks.|
|Mar-13-07|| ||chancho: <cionics> After 86.Kxh6 the Black King has no moves.(stalemate)|
|Mar-14-07|| ||cionics: Duh! Thanks, Chancho.|
|Mar-15-07|| ||YouRang: <cionics><Also, what is the meaning of a "tablebase draw".>|
A "tablebase" is a computer-generated exhaustive table of certain chessgame endings. For example, it is not hard to find an online tablebase that covers all endings with 6 or fewer pieces (where the king, pawns, and everything else counts as a "piece").
With such a tablebase, you can give it any legal position with 6 or fewer pieces (and tell it whose turn to move), and it will tell you the "state" of that position.
Every such position is in exactly one of 3 states:
(1) white can force a win
(2) black can force a win
(3) the side to move can force a draw.
The tablebase will tell you what the state is for the given position, AND tell you what state you will obtain for each legal move that can be made in that position. Hence, the tablebase, used iteratively, will tell you how to force a win (if possible), or how to preserve the draw (if possible).
If either side can force a win, it also tells you how many moves until mate. This position is a "tablebase win" or a "tablebase loss", depending on whose turn to move.
If neither side can force a win (i.e. state 3 above), the position is a "tablebase draw".
BTW, I don't think any tablebases allow castling -- they assume that castling rights are gone. Also, you can't give it an initial position where capturing en passant is possible.
|Mar-16-07|| ||cionics: Yourang,
Thanks for the very complete answer. I always appreciate your posts, by the way. But, I must say, I often picture you as looking like your icon which is kind of scary!
|Mar-24-07|| ||Fisheremon: <al wazir: I still think white had a win on move 67.> Sure as 67.a5 could do and seemed to be the last (theoretical) winning chance for White.|
|Mar-30-07|| ||gambitfan: A superb stalemate obtained as the game looks lost!|
|Oct-14-09|| ||crosscheck: What is wrong with 84. Qg7+. That seems to do it. That takes off the queens! Surely white can win the pawn ending?|
|Oct-15-09|| ||Eduardo Leon: <crosscheck>, unfortunately, after <84. Qg7+?>, black gets the opposition and, thus, the draw:|
<84. Qg7+ Qxg7 85. hxg7+ Kxg7 86. Kg4> (<86. Kh4 Kh6>) <86. ... Kg6>.
|Mar-27-15|| ||Mateo: It seems to me that 57.Qe3 (?) was wrong. 57...Qxe3 (!) (instead of 57...Qc2 (?)) 58.fxe3 should be a draw. Of course, White has an extra pawn. But after 58...Kg6 59.Kg1 (or Kg2) Kf5 60.Kf2 Ke4 61.Ke2 f5, Black seems to hold. Interesting ending.|
|Mar-27-15|| ||Retireborn: <Mateo> Houdini agrees that your line should draw. Very interesting is 59.e4 (instead of Kg1 or Kg2) f5! 60.exf5+ Kxf5 and now 61.b4 is the only move to draw, as 61.Kg2 Ke4 62.Kf2 Kd3! would even win for Black(!)|
In my mind this game is always linked with the finish of Spassky vs Keres, 1961
Spassky learned that lesson well.
|Mar-28-15|| ||Compound Error: ♕e3 or ♕xe3? That is the question|
|Mar-28-15|| ||SimonWebbsTiger: For what it's worth, Ribli annotated the game back in Informator 40/53.|
In the line 57...Qxe3, he analysed 59. e4 to a win for black and 58...Kg6 59.Kg2 Kf5 60.Kf2 Ke4 61.Ke2 f5 62.b4 as a win.
|Apr-02-15|| ||Mateo: <SimonWebbsTiger>. I think Ribli is wrong. For instance, 62...axb4 63.a5 Kd5 64.a6 Kc6 65.Kd3 Kb6 66.Kc4 Kxa6 67.Kxb4 Kb6 68.Kc4 Kc6 69.Kd4 Kd6 70.e4 fxe4 71.Kxe4 Ke6 72.Kf4 Kf6. This is a draw.|
|Apr-03-15|| ||Howard: According to Ribli's notes in the Informant, he allegedly missed a win around the 83rd move, but he was apparently wrong--correct ?|
|Apr-03-15|| ||Mateo: <Howard> Yes. Ribli was winning but he missed the win: 85.Kg5?? was a blunder instead of 85.Qh3.|
|Apr-03-15|| ||Howard: Presumably, the tablebase will back up that assertion.|
|Sep-05-17|| ||Olavi: 85.Qh3 is still a draw, as are most 'normal' g+h-pawn endings. This was well known before tablebases, but perhaps people didn't pay attention.|
< Earlier Kibitzing · PAGE 4 OF 4 ·