Did Anand miss a win in Game 3?

[Houdini]

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]

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

[Dr.Wael Deeb]

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
Best regards,
Dr.D

[Eelco de Groot]

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

[marcelk]

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.

[Houdini]

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]

[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

[Houdini]

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 .
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]

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]

[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