Mar-30-12
 | | tamar: Near brilliancy. 27 Nh4 is just so strange.
After seeing the long range sacrifice on f6, and with it the subsequent sacrifice on f7, Hou misses 27 Qh4 with inevitable mate. |
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| Mar-30-12 | | rannewman: could you give the exact line? |
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| Mar-30-12 | | wordfunph: <rannewman>
Hou - Jianchao
after 26...Bf8
click for larger viewi'm not an expert in using engines, but mate in 16..
Analysis by Fritz 11:
 (#17): 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Rxh2 30.Qf6 Rh3+ 31.Kg4 gxf5+ 32.Kxh3 |
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| Mar-30-12 | | wordfunph: oopppsss, in 17 moves.. |
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Mar-30-12
 | | HeMateMe: White could give up her Knight for the pawn because black doesn't control the h1 queening square with his wrong color Bishop. Nice job by Yifan, 2 draws so far, but two losses. Tough competition. I bet Polgar would love this tournament, very tactical, fighting chess. Judit style chess, not the 50% draw crap we see at so many other events. |
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Mar-30-12
 | | AylerKupp: An interesting change of heart. After playing aggressively for a win for the first 34 moves she begins to play just as aggressively for a draw with 35.Rb8. |
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Mar-30-12
 | | Penguincw: The two leaders* draw their game.
*As in cellar leaders, as I believe these players entered the round, at the bottom of the standings. |
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| Mar-30-12 | | luzhin: Yes, it's very odd that Hou didn't play 27.Qh4. I can only assume she didn't see a mate after 27...Kxf7 but it's there, alright: 28.Ne7+! Ke6 29.Qe4+ Kd7 30.Qxb7+ Ke6 31.Qd5+ Kxe7 32.Rf7++. |
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| Mar-30-12 | | twinlark: I was watching this game live and she was under extreme time pressure from move 20 onwards. |
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| Mar-31-12 | | Ladolcevita: Actually both of them are so,as I heard from some chess fans here,reliable sources I shall say:)
And indeed,Yifan should have easily spotted the expected move otherwise... |
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Mar-31-12
| | AylerKupp: Mates found by engines (Part 1 of 2)
<wordfunph> I'm not an expert at using engines either, so I will try to compensate for it by volume. :-) Here's what some other engines claim after 26...Bf8. It looks like a mate in 12 is the shortest so thought it would be interesting to find out how deep the engines had to search to find the 12-move mate and how long it took them on my computer using my setup (Intel Q9400, 32-bit, 4-core, 4 GB RAM, 1024 MB hash table, Arena 3.0 GUI, Infinite Analysis mode, and displaying 5 PVs). Note that Komodo 3.0 is a single-core engine so until a multi-core version is available if you want to use it it's probably best to plan on running it overnight, although see the note below.
click for larger viewCritter 1.4: [+M12], d=24, 1:04:35: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Kxe2 gxf5 31.Rxf5+ Kg8 32.Qf6 h6 33.Qg6+ Kh8 34.Rf7 Re8+ 35.Kd1 Re1+ 36.Kxe1 Bb4+ 37.Kd1 b5 and of course 38.Qg7# or 38.Qh7# but Critter didn't list the actual last move even though it counted in the mate count. Houdini 1.5a: [+M12], d=22, 00:06:17: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Kxe2 gxf5 31.Rxf5+ Kg8 32.Qf6 h6 33.Qg6+ Kh8 34.Rf7 Re8+ 35.Kf3 Re3+ 36.Kxe3 Bc5+ 37.Kf3 a5 38.Qg7#. A slightly different way of getting there than Critter but at least Houdini listed the last move. Although technically it listed 38.Qg7+ but this may be an Area issue and not Houdini's. Komodo 3.0: Komodo stopped calculating at d=21 after it found a mate in 20 even though it kept counting the elapsed time. Tried it 3 times on 2 different computers with similar results although on the 3rd attempt (on a different computer), Komodo stopped calculating at d=21 without finding a mate (and after searching fewer nodes). Rybka 4.1: [+M12], d=17, 00:07:52: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Kxe2 gxf5 31.Rxf5+ Kg8 32.Qf6 Re8+ 33.Kd1 h6 34.Qf7+ Kh8 35.Qxe8 Kg7 36.Qxf8+ Kh7 37.Qe7+ Kh8 38.Rf8#. Yet another way to force the 12-move mate, although, like Houdini, the last move listed was 38.Rf8+. Spike 1.4: [+M12], d=23, 00:06:30: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Kxe2 gxf5 31.Rxf5+ Kg8 32.Qf6 Re8+ 33.Kf3 h6 34.Qg6+ Kh8 35.Rf7 Re3+ 36.Kxe3 Bc5+ 37.Ke4 b5. Again a slightly different way (33.Kf3 instead of 33.Kf1 like Rybka) and the last move (38.Qg7# or 38.Qh7#) wasn't listed. Stockfish 2.2.2: [+M12], d=25, 01:02:40: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Kxe2 Re8+ 31.Ne7+ Ke6 32.Qe4+ Kd7 33.Qxb7+ Kd6 34.Rf6+ Ke5 35.Qxa6 Bxe7 36.Qe6+ Kd4 37.Qe4+ Kc5 38.Qc4#. This time a major deviation, 31.Ne7+, and the last move listed as 38.Qc4+. All somewhat similar in that, like Fritz 11, they selected 27...Qxg2+ and 28...Re2+ as desperation moves to try to avoid the inevitable as long as possible (the horizon effect) and similar desperation moves at the end. Each engine found different ways to get to mate but none found a quicker mate than 12 moves, at least not in the time that I let them run . And after 27...Qxg2+ White obviously has a won game anyway so the actual mating line is not of any practical value. So the "winner" in this case was Houdini 1.5a since it found the minimum-move mate the quickest. But on another computer with a different setup there may be a different "winner". I don't know what to say about Stockfish. It started generating evals over [+20.00] as early as d=14 and 00:00:03 and reached evals over [+80.00] by d=22 and 00:01:03 but didn't announce mate until d=25, 01:02:40, and then it was the shortest mate. <wordfunph> Out of curiosity, did you notice at what depth Fritz 11 found the 17-move mate? And, if you run the analysis again, I would be curious to find out at what depth it found the 12-move mate or whether it showed the "Komodo effect". |
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Mar-31-12
| | AylerKupp: Mates found by engines (Part 2 of 2)
Another way of looking at it is to see when the engine found the first mate. After all, mate is mate and you don't get any more points (other than perhaps bragging rights) for finding it sooner. So here are the results, mercifully without commentary: Critter 1.4: [+M22], d=20, 00:02:37: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Qxh7+ Ke6 31.Kxe2 Re8 32.Ne3 Be7 33.Qxg6+ Kd7 34.Qe4 Rc8 35.Rf7 Re8 36.Qxb7+ Kd6 37.Nf5+ Ke6 38.Qb3+ Kd7 39.Qd5+ Kc7 40.Nxe7 Kb8 41.Qd6+ Ka7 42.Qc7+ Ka8 43.Qc6+ Kb8 44.Qxe8+ Kc7 45.Nd5+ Kd6 46.Rf6+ Kxd5 47.Qe4+ Kc5 48.Qc4+ Houdini 1.5a: [+M25], d=18, 00:00:35: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Qxh7+ Ke6 31.Qxg6+ Kd7 32.Kxe2 Re8+ 33.Kf3 Bc5 34.Qf7+ Kd8 35.Qxb7 Rh8 36.Qd5+ Kc7 37.Qxc5+ Kb8 38.Qe5+ Ka7 39.Qd4+ Kb7 40.Qxh8 a5 41.h4 Kb6 42.h5 a4 43.Qd4+ Ka6 44.Qxa4+ Kb7 45.Qa5 Kc8 46.Qc5+ Kd7 47.Re1 Kd8 Komodo 3.0: [+M20], d=21, 00:52:59: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kh3 Kxf7 30.Qxh7+ Ke8 31.Qxb7 gxf5 32.Qxa8+ Kd7 33.Qxf8 Re3+ 34.Kh4 Re5 35.Qf7+ Re7 36.Qd5+ Kc8 37.Qxf5+ Kb7 38.Qd5+ Ka7 39.Qd4+ Ka8 40.Rf8+ Kb7 41.Qb4+ Kc7 42.Qxe7+ Kc6 43.Rf5 a5 44.Rc5+ Kb6 45.Qc7+ Ka6 46.Rxa5+ Rybka 4.1: [+M16], d=14, 00:03:05: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Qxh7+ Ke6 31.Nd4+ Kd6 32.Qxb7 Re3+ 33.Kg4 Rd8 34.Rf6+ Ke5 35.Re6+ Kxd4 36.Qb6+ Kxd3 37.Qxe3+ Kc4 38.Rc6+ Kd5 39.Qe6+ Kd4 40.Kf3 Re8 41.Rc4+ Kd3 42.Qd5+ Spike 1.4: [+M15], d=20, 00:01:52: 27.Qh4 Qxg2+ 28.Kxg2 Re2+ 29.Kf3 Kxf7 30.Qxh7+ Ke8 31.Kxe2 Rc8 32.Qxg6+ Kd8 33.Qf6+ Kd7 34.Qf7+ Kc6 35.Qe6+ Kc7 36.Rc1+ Kb8 37.Rxc8+ Ka7 38.Rxf8 a5 39.Nd4 b5 40.Rf7+ Kb8 41.Qe8+ Stockfish 2.2.2: [+M12], d=25, 01:02:40 above was the first mate found. So the "winner" in this case was again Houdini 1.5a who found a mate in only 00:00:35. |
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| Apr-03-12 | | Rook e2: Does anyone know why this line is called 'Amsterdam variation'? |
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Apr-03-12
| | AylerKupp: <Rook e2> No idea but it was probably made popular in a tournament played in Amsterdam, like the Scheveningen variation. Interestingly, Wikipedia says that in The Oxford Companion to Chess the Amsterdam variation is the name for the following Sicilian Dragon variant: 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 Bg7 7.Be2 Nc6 8.<Qd2>. |
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| Apr-03-12 | | Rook e2: Yes I noticed when googling that there is a sicilian-dragon Amsterdam variation also.. I believe I read somewhere that the scheveningen variation was origionally named after Euwe but that it was his wish to call it the 'Scheveningen'. |
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| Apr-03-12 | | twinlark: <Ladolcevita: Actually both of them are so,as I heard from some chess fans here,reliable sources I shall say:) And indeed,Yifan should have easily spotted the expected move otherwise...> Indeed they were both under time pressure, but Hou only had seconds where Zhou had minutes. I'm not sure that sort of criticism is warranted in any event. More to the point, as shown in subsequent games, is Hou's poor time management and the fact that after move 40 the players seems to be operating only on time increments, which does not make for great chess. |
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Apr-04-12
| | tamar: If I remember correctly, Hou made the move 21 Rxf6 fairly quickly. The rook cannot be taken, but the variations are not trivial If 21...gxf6 22 b4! (Cutting off the Queen from the g4 square) Qa2 (Black has to give up the bishop, if 22...Bf8 23 Qe4 Qd7 24 Qxh7+ Kf8 25 Rf1 (25 Bh6 is only a draw) Qd7 26 Bh6 Bxh6 27 Qxh6+ Ke7 28 Qxf6+ Kd6 29 Nf5+ Kc7 
click for larger viewHere Hou would have to see that the King is not getting away 30 Qe5+ Kd8
31 Nd6 Re7 32 Be4 wins, as the d file is opened for the rook and b7 is attacked. Zhao Jianchao avoided all this with 21...Bc4, but Hou found a way to avoid retreating her rook and also to activate her knight with the star moves 25 Nf5 and 26 Rxf7 26...Bf8 should have lost outright to 27 Qh4, but most of Hou's attention had to go to 26...Kxf7, taking the rook, as White gets an attack, but it is difficult to see how she finishes it. After 26...Kxf7 27 Qc7+ Ke6 28 Ng7+ Kd5
click for larger view Not so easy, for instance my candidate move 29 Qxb7+ just loses for White, but Houdini confirms that White is definitely winning. I am thinking 26...Bf8 was such a surprise that it momentarily confused Hou, and she made a "safe" move protecting her pieces instead of the killer 27 Qh4. Overall, a great game by Hou marred by a timid 27th move. |
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Kibitzing
