Did Anand miss a win in Game 3?

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Houdini
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Re: Did Anand miss a win in Game 3?

Post by Houdini » Mon May 14, 2012 9:21 pm

Jack Lad wrote:6. Kxa5? is a blunder. White needs to play Kb6! instead to win.
[d] 8/1p1PR2p/1K4k1/p4p2/7R/1P3P2/1r1r2P1/8 b - - 3 6
Yes, that's a very nice variation, white playing Kb6! and Kc7.

kgburcham
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Re: Did Anand miss a win in Game 3?

Post by kgburcham » Mon May 14, 2012 9:26 pm

Dr.Wael Deeb wrote:
kgburcham wrote:
Dr.Wael Deeb wrote:Again as I wrote above without even using a chess engine,Mr.Houdini has rushed a little bit so early to claim that Anand had missed an easy win....
Dr.D
I went back to see the "Easy Win" words, could not find them.
All I could find that Robert said is this:
"Instead of Anand's 34.Rc7 the alternative 34.d7! looks very promising."

with Roberts high chess rating, strong hardware, strong program, and programming ability, I didnt think he would say "easy win".
This group has run off most all programmers, I hate to lose another programmer, but if Robert dissappears, I will still read here.
kgburcham
So what Should I do :!: :?:
why do you have to do anything?
Build a statue of Robert and get down on my knees because he's a programmer :!: :?:
no one else does this
Sticking to the same logic,where were you when Don or the so called Mr.Komodo called me Dweeb without no reason of whatever :!: :?:
ok I agree, some should have spoke up
I treat people by their kindness or by their nasty nature....Robert is definitely in the second group and if he wants to leave then let it be....
I thought maybe I missed something that happened between you two, not sure. Maybe it is the code issues. I havent seen the nasty nature you are talking about. The fans are always here, the programmers are temporary.
Dr.D

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Dr.Wael Deeb
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Re: Did Anand miss a win in Game 3?

Post by Dr.Wael Deeb » Mon May 14, 2012 9:39 pm

kgburcham wrote:
Dr.Wael Deeb wrote:
kgburcham wrote:
Dr.Wael Deeb wrote:Again as I wrote above without even using a chess engine,Mr.Houdini has rushed a little bit so early to claim that Anand had missed an easy win....
Dr.D
I went back to see the "Easy Win" words, could not find them.
All I could find that Robert said is this:
"Instead of Anand's 34.Rc7 the alternative 34.d7! looks very promising."

with Roberts high chess rating, strong hardware, strong program, and programming ability, I didnt think he would say "easy win".
This group has run off most all programmers, I hate to lose another programmer, but if Robert dissappears, I will still read here.
kgburcham
So what Should I do :!: :?:
why do you have to do anything?
Build a statue of Robert and get down on my knees because he's a programmer :!: :?:
no one else does this
Sticking to the same logic,where were you when Don or the so called Mr.Komodo called me Dweeb without no reason of whatever :!: :?:
ok I agree, some should have spoke up
I treat people by their kindness or by their nasty nature....Robert is definitely in the second group and if he wants to leave then let it be....
I thought maybe I missed something that happened between you two, not sure. Maybe it is the code issues. I havent seen the nasty nature you are talking about. The fans are always here, the programmers are temporary.
Dr.D
Thanks for your civilized response :D
Best regards,
Dr.D
_No one can hit as hard as life.But it ain’t about how hard you can hit.It’s about how hard you can get hit and keep moving forward.How much you can take and keep moving forward….

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Eelco de Groot
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Re: Did Anand miss a win in Game 3?

Post by Eelco de Groot » Mon May 14, 2012 10:00 pm

At depth 28 the eval has gone up a little. It could be, with mainly Rooks involved a situation where you can only make small progress, I don't know. Most of the players here will be stronger than me and certainly Robert he is a 2100+ Fide rating. But regarding the output, combined with the usual variation in scores, I don't think I can see it just letting the program add one more iteration. But I will try at least to go to depth 29, may take a few hours though, because this is with just 256 Mb hash, 75 % of the Q6700 available. If you go too deep, > 1000 minutes I think the reliability of the hash contents is not so good anymore, so the usefullness of 31+ iterations is a bit doubtful in itself. With very good position learning learning or maybe separate storage of PV nodes in their own transposition table maybe that could be improved. That is just a hypothesis though.


28/72 87:18 +1.32++ 34.d7 Rcc2 35.Rc4 Rb2+ 36.Kc1 Rxa2
37.Rc7 f4 38.Rxb7 (14.442.826.367) 2756

28/72 118:45 +1.40 34.d7 Rcc2 35.Rc4 (19.804.729.682) 2779
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan

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marcelk
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Re: Did Anand miss a win in Game 3?

Post by marcelk » Mon May 14, 2012 10:19 pm

Houdini wrote:
notyetagm wrote:From the comment thread over at Chess Vibes http://www.chessvibes.com/reports/anand ... r-37-moves
In the press conference, they analyzed a nice line that at the end with a rook sac and queen with check. This was 34.d7 Rcc2 35.Rc4 Rb2+ 36.Kc1 Rxa2 37.Rc8 Rf2 (Threatening mate on f1 or a1) 38. Re6+! Kf7 39.Rf6!! wins. So Vishy had not seen this resource and hence dint play 34.d7. A pity. But a nice fighting game :)
He'll be disappointed to have missed a good opportunity - he didn't have a lot of time left on the clock.

After 34.d7! there appear to be 3 main defenses for black:
1) 34...Rcc2 35.Rc4 Rxc4 36.bxc4
2) 34...Rd1+ 35.Kb2 Rd2+ 36.Ka3 Rcc2
3) 34...Rd1+ 35.Kb2 Rc5 36.Rexh7 Rd2+

So far in each line Houdini gives a score above +0.9 at depth 35 or higher.
Not sure whether it's a win, but it's certainly very promising.
My engine doesn't go to 35 ply in a reasonable amount of time.
1. d7 is favored from depth 1 to 21, eval starting from 2.1 trending down to 1.7, all PVs as "d7 Rd1+, Kb2 Rd2+, Ka3 Rcc2, Ka4 Rxa2+, Kb5".
From depth 22, 1. Rc4 takes over (but continues trending down to +1.3 at 24 ply at which point I stopped the program).
My expectation is that it is a draw. Rook endings with 1 pawn difference can be hard to win.

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Houdini
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Re: Did Anand miss a win in Game 3?

Post by Houdini » Mon May 14, 2012 10:39 pm

marcelk wrote:
Houdini wrote: He'll be disappointed to have missed a good opportunity - he didn't have a lot of time left on the clock.

After 34.d7! there appear to be 3 main defenses for black:
1) 34...Rcc2 35.Rc4 Rxc4 36.bxc4
2) 34...Rd1+ 35.Kb2 Rd2+ 36.Ka3 Rcc2
3) 34...Rd1+ 35.Kb2 Rc5 36.Rexh7 Rd2+

So far in each line Houdini gives a score above +0.9 at depth 35 or higher.
Not sure whether it's a win, but it's certainly very promising.
My engine doesn't go to 35 ply in a reasonable amount of time.
1. d7 is favored from depth 1 to 21, eval starting from 2.1 trending down to 1.7, all PVs as "d7 Rd1+, Kb2 Rd2+, Ka3 Rcc2, Ka4 Rxa2+, Kb5".
From depth 22, 1. Rc4 takes over (but continues trending down to +1.3 at 24 ply at which point I stopped the program).
My expectation is that it is a draw. Rook endings with 1 pawn difference can be hard to win.
In the PV you mention 34. d7 Rd1+ 35.Kb2 Rd2+ 36.Ka3 Rcc2 37.Ka4 Rxa2+ 38. Kb5, after 38...Rab2 white wins with the maneuver Kb6! and Kc7! - a very nice variation.
Alternatives at black's move 38 are not better, at depth 24 the score is over +2.

In other variations very often White ends up 2 pawns ahead.Here's an example from my defense 1):

Code: Select all

37/83  74:54  +0.85    34.d7 Rcc2 35.Rc4 Rxc4 36.bxc4 h5 37.Kc1 Rd4
                       38.Kc2 Kf6 39.Rh7 Kg6 40.Kc3 Rd1 41.d8Q Rxd8 
                       42.Rxb7 Rd1 43.Rb2 Kf6 44.c5 Ke6 
                       45.Kc4 Kd7 46.a4 Kc7 47.Kb5 h4 
                       48.Re2 Rb1+ 49.Kxa5 Kc6 50.Re6+ Kxc5 
                       51.Rf6 Rg1 52.Rxf5+ Kc6 (27.478.478.730) 6113 
                       TB:669.617 
The final position of this line is:
[D]8/8/2k5/K4R2/P6p/5P2/6P1/6r1 w - -
This is won for white, but maybe black has a better defense somewhere. Odds are pretty good for white, though :).

kgburcham
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Re: Did Anand miss a win in Game 3?

Post by kgburcham » Mon May 14, 2012 11:11 pm

[D] 2r5/1p2R2p/3P2k1/p4p2/7R/1P3P2/P2r2P1/1K6 w - - 0 1

Deep Rybka 4.1
hash 4096
12 cores

1.d7 Rcc2 2.Rc4[] Rxc4 3.bxc4[] h5 4.Kc1[] Rd4 5.Kc2 Kf6 6.Rh7[] Kg6 7.Kc3[] Rd1 8.d8Q Rxd8 9.Rxb7 Kf6 10.c5 Rd5 11.Rb5 h4 12.a4 Rd1 13.Rxa5 Rc1+ 14.Kd4 Rd1+ 15.Kc4 Rg1 16.Ra6+
+- (2.10) Depth: 30 01:31:40 5381mN, tb=122475

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Houdini
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Re: Did Anand miss a win in Game 3?

Post by Houdini » Mon May 14, 2012 11:20 pm

Chessbase gives: "But Black defends with 34.d7 Rcc2 35.Rc4 Rxc4 36.bxc4 h5 37.Kc1 Rd4 38.Kc2 Kf6 39.Rh7 Ke6 40.Kc3 Rxd7 41.Rxh5 Rg7"

So superficial :lol:.
40.Kb3! seals the deal for White.

[D]8/1p1P3R/4k3/p4p1p/2Pr4/5P2/P1K3P1/8 w - -

Code: Select all

Engine: Houdini DEV 3T (4096 MB)
by Robert Houdart

31/70  4:49   +1.93    40.Kb3 Kf6 41.c5 h4 42.Kc3 Rd1 43.a4 Kg6 
                       44.d8R Rxd8 45.Rxb7 Rd1 46.Rb2 Kf6 
                       47.Kc4 Ke6 48.Kb5 Kd7 49.Kb6 Kc8 
                       50.Kxa5 Kc7 51.Kb5 Rd8 52.Kc4 Rd1 
                       53.a5 (1.929.082.747) 6659 TB:1.867
Again White ends up with 2 bonus pawns.

Dan Andersson
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Re: Did Anand miss a win in Game 3?

Post by Dan Andersson » Mon May 14, 2012 11:49 pm

After 40. Kb3 playing out the pawn endgame after 40. .. Rxd7 is pretty forcing as well as illuminating ;) The superficial quip makes me wink impishly.

MvH Dan Andersson

kgburcham
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Re: Did Anand miss a win in Game 3?

Post by kgburcham » Tue May 15, 2012 12:00 am

[D] 8/1p1P3R/4k3/p4p1p/2Pr4/5P2/P1K3P1/8 w - -

35/72 4:43 +2.42

40.Kc3 Rxd7 41.Rxd7 Kxd7 42.Kd4 Ke6
43.f4 b6 44.c5 b5 45.c6 Kd6 46.c7 Kxc7
47.Kc5 b4 48.Kb5 Kd6 49.Kxa5 Kc5
50.g3 Kc4 51.Kb6 Kd4 52.Kb5 Kc3
53.Kc5 (10.085.214.180) 35623 TB:10.524

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