[Computer-go] AlphaGo won first game!

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Hiroshi Yamashita

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Mar 9, 2016, 2:43:31 AM3/9/16
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AlphaGo won 1st game against Lee Sedol!

Hiroshi Yamashita

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Michael Alford

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Mar 9, 2016, 2:46:22 AM3/9/16
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It's true, saw it with my own eyes.

Hiroshi Yamashita

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Mar 9, 2016, 2:46:40 AM3/9/16
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sgf

(;GM[1]SZ[19]
PB[Lee Sedol]
PW[AlphaGo]
RE[W+R]
KM[7.5]DT[2016-03-09]TM[7200]RU[Chinese]
;B[qd];W[dd];B[pq];W[dp];B[fc];W[cf];B[ql];W[od];B[ld];W[qc]
;B[rc];W[pc];B[re];W[of];B[pg];W[og];B[ph];W[id];B[lf];W[oh]
;B[pi];W[lh];B[kh];W[ke];B[le];W[lg];B[kg];W[kf];B[ne];W[oe]
;B[jc];W[ic];B[jd];W[ie];B[je];W[jf];B[if];W[jg];B[li];W[mi]
;B[hf];W[ih];B[mb];W[gd];B[ki];W[mj];B[kk];W[ib];B[ob];W[ml]
;B[lm];W[nc];B[nb];W[kb];B[lc];W[mm];B[ln];W[kl];B[ll];W[lk]
;B[jj];W[jl];B[hj];W[hi];B[gj];W[gf];B[ii];W[jh];B[ij];W[mn]
;B[lo];W[mo];B[lp];W[mp];B[lq];W[mq];B[im];W[qo];B[fq];W[gg]
;B[cn];W[dn];B[dm];W[fp];B[gp];W[gq];B[fr];W[co];B[en];W[do]
;B[ep];W[cm];B[dl];W[lr];B[kr];W[rb];B[jb];W[ja];B[mf];W[mh]
;B[nd];W[qj];B[pj];W[qk];B[pl];W[pk];B[ok];W[rh];B[rl];W[qf]
;B[ri];W[rf];B[pf];W[qe];B[qh];W[cc];B[bn];W[bm];B[bl];W[bo]
;B[rg];W[mr];B[po];W[jr];B[kq];W[pn];B[oo];W[qp];B[on];W[pp]
;B[op];W[qq];B[or];W[pr];B[oq];W[pd];B[qr];W[rr];B[ps];W[rs]
;B[rn];W[ro];B[qn];W[so];B[cl];W[an];B[ks];W[om];B[ol];W[ci]
;B[hh];W[hg];B[dr];W[dj];B[bq];W[cq];B[cr];W[bp];B[dq];W[br]
;B[cp];W[ap];B[ek];W[fi];B[bj];W[bi];B[pb];W[qb];B[sf];W[rd]
;B[ai];W[ah];B[aj];W[bh];B[gi];W[fj];B[fk];W[oc];B[mc];W[cj]
;B[al];W[nm];B[pm];W[aq];B[gh];W[fh])

René van de Veerdonk

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Mar 9, 2016, 2:46:45 AM3/9/16
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wow .. congrats to the AlphaGo team!!

Jim O'Flaherty

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Mar 9, 2016, 2:49:56 AM3/9/16
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Congratulations, AlphaGo and team. And by resignation! That's fantastic!

Anyone know where the tipping point was? Did Sedol get the end game order just slightly off and AlphaGo took advantage? Or was their an earlier poor move by Sedol and/or surprising (and good) move by AlphaGo? I'm WAY too weak a player to even make stupid guesses. Any links to in depth analysis would be greatly appreciated!

Marc Landgraf

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Mar 9, 2016, 2:55:50 AM3/9/16
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It was pointed out by Lee Sedol after the game and Kim Myungwan during
the game, that Q5 should have been better at R4. I would say this was
the final stage of the middle game. The result from the game left Lee
Sedol with an unwinnable endgame. And "by resignation" is meaningless
here. It is just a matter of personal preference if pros resign heir
close games, even if their are lost by 0.5 or if they decide to
resign. In this game most counts had AlphaGo 3-6 points ahead.

Tobias Pfeiffer

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Mar 9, 2016, 3:26:20 AM3/9/16
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Wow, congrats to the AlphaGo team! Would love to see a more detailed analysis later today.

Sergey Nikolenko

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Mar 9, 2016, 3:27:58 AM3/9/16
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Everybody here probably knows it, but just in case -- there's a
commented broadcast uploaded here:
http://www.youtube.com/watch?v=vFr3K2DORc8
I don't play well enough to understand how good the commentary is, though.

With best regards,
Sergey Nikolenko.

Igor Polyakov

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Mar 9, 2016, 3:30:06 AM3/9/16
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The amount of points AlphaGo was ahead is also meaningless because it
started playing slow moves when it got ahead. After the big fights were
finished it already knew it was going to win easily.

David Fotland

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Mar 9, 2016, 3:31:16 AM3/9/16
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Many Faces thought alpha go was ahead most of the game.  It looked to me like the turning point was when Alphago cut in the center then gave up the two cutting stones for gains on both sides (but not so strong…). 

 

Congratulations Aja!

 

I watched it at Google in Mountain View with about 100 people.

 

David

Marc Landgraf

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Mar 9, 2016, 3:56:53 AM3/9/16
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Btw, is there any information on what hardware AlphaGo is running. And
how does it compare to the version used against Fan Hui?

Julian Schrittwieser

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Mar 9, 2016, 3:57:51 AM3/9/16
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As Demis said during the press conference, it's roughly the same amount of hardware.

"Ingo Althöfer"

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Mar 9, 2016, 5:02:01 AM3/9/16
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Congrats to the AlphaGo team also from me!
 

Von: "David Fotland" <fot...@smart-games.com>
> Many Faces thought alpha go was ahead most of the game. 

Similar with CrazyStone. After move 26 CS gave 56 % for AlphaGo
and never went below this value. Soon later it were 60+ %, and
never went lower, too.

Ingo.

Darren Cook

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Mar 9, 2016, 6:55:01 AM3/9/16
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Wow - didn't expect that. Congratulations to the AlphaGo team!

Ingo wrote:
> Similar with CrazyStone. After move 26 CS gave 56 % for AlphaGo
> and never went below this value. Soon later it were 60+ %, and
> never went lower, too.

Did it show jumps at some of the key moves the human experts thought
were decisive? (E.g. white 80, then 84-88 as poor, then either black 119
or black 123 as the losing move):
https://gogameguru.com/alphago-defeats-lee-sedol-game-1/

(I guess the "reversal" at white 136 was just an MCTS program knowing it
is ahead, and playing for probability, not winning margin.)

I.e. is it fair to say that other computer programs will appreciate and
understand the computer's moves better than the human's moves, so saying
it is ahead is to be expected? (confirmation bias)

Darren

P.S. Lee Sedol says he was shocked, and never expected to lose, even
when he was behind. I wonder if he did any special preparation for this
match? (E.g. playing handicap games against other strong MCTS program,
to appreciate how they behave when they have a lead.)

Olivier Teytaud

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Mar 9, 2016, 7:00:46 AM3/9/16
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Congratulations to AlphaGo people!

Are there strong humans who have an opinion, on whether this advantage at move 26
is real ?

In pro games, does it happen often that there is a clear advantage at move 26 ?




--
=========================================================
"I will never sign a document with logos in black & white." A. Einstein
Olivier Teytaud, olivier...@inria.fr, http://www.slideshare.net/teytaud



Xavier Combelle

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Mar 9, 2016, 8:35:26 AM3/9/16
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Congrats to Aja and alphago team

Xavier Combelle

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Mar 9, 2016, 8:36:30 AM3/9/16
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This comment should be very good, it was done by a 9 dan pro, the top rank in go.


Hiroshi Yamashita

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Mar 9, 2016, 9:54:16 AM3/9/16
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Aya also thought AlphaGo was ahead 55% - 65% most of game.
But it is because Aya thought Black N-18 group is 65% alive at move 75.
This Black must live 100%. So I think MCTS tend to think White is ahead.
I'm curious whether AlphaGo understands this group is over 80% alive.

Thanks,
Hiroshi Yamashita

----- Original Message -----
From: ""Ingo Althöfer"" <3-Hirn...@gmx.de>
To: <compu...@computer-go.org>
Sent: Wednesday, March 09, 2016 7:01 PM
Subject: Re: [Computer-go] AlphaGo won first game!

Richard Lorentz

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Mar 9, 2016, 11:13:30 AM3/9/16
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I found Michael Redmond's commentary very good. Helped a weak player like me understand what was going on, but occasionally went over my head, which I'm sure others appreciated. He came across as a class act.

His partner, on the other hand, (I forget his name) was more of a hindrance to the presentation than anything. Towards the end of the game I found him downright annoying.

-Richard


Gonçalo Mendes Ferreira

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Mar 9, 2016, 11:24:59 AM3/9/16
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You may also want to check out AGA's commentary by Andrew Jackson and
Myungwan Kim. They don't run out of magnetic stones.

https://www.youtube.com/watch?v=YZPKR7HzM_s

On 09/03/2016 16:13, Richard Lorentz wrote:
> I found Michael Redmond's commentary very good. Helped a weak player
> like me understand what was going on, but occasionally went over my
> head, which I'm sure others appreciated. He came across as a class act.
>
> His partner, on the other hand, (I forget his name) was more of a
> hindrance to the presentation than anything. Towards the end of the game
> I found him downright annoying.
>
> -Richard
>
>
>

"Ingo Althöfer"

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Mar 9, 2016, 11:30:17 AM3/9/16
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Hello,

I had the honour to watch round 1 of the match together with FJ Dickhut
(German 6-dan; player in the codecentric Challenges 2014 and 2015) and
Andreas Fecke (3-dan; Go cartoonist: "Stones").

Here are some photos with comments:
http://althofer.de/lee-sedol-alphago-round-1.html

Ingo.

Petr Baudis

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Mar 9, 2016, 12:11:14 PM3/9/16
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Hi!

On Wed, Mar 09, 2016 at 04:43:23PM +0900, Hiroshi Yamashita wrote:
> AlphaGo won 1st game against Lee Sedol!

Well, I have to eat my past words - of course, there are still four
games to go, but the first round does not look like a lucky win at all!

Huge congratulations to the AlphaGo team, you have done truly amazing
work, with potential to spearhead a lot of further advances in AI in
general! It does seem to me that you must have made a lot of progress
since the Nature paper though - is that impression correct?

Do you have some more surprising breakthroughs and techniques in store
for us, or was the progress mainly incremental, furthering the training
etc.?


By the way, there is a short snippet in the paper that maybe many
people overlooked (including me on the very first read!):

> We introduce a new technique that caches all moves from the search
> tree and then plays similar moves during rollouts; a generalisation of
> the last good reply heuristic. At every step of the tree traversal, the
> most probable action is inserted into a hash table, along with the
> 3 × 3 pattern context (colour, liberty and stone counts) around both the
> previous move and the current move. At each step of the rollout, the
> pattern context is matched against the hash table; if a match is found
> then the stored move is played with high probability.

This looks like it might overcome a lot of weaknesses re semeai etc.,
enabling the coveted (by me) information flow from tree to playouts, if
you made this to work well (it's similar to my "liberty maps" attempts,
which always failed though - I tried to encode a larger context, which
maybe wasn't good idea).

Would you say this improvement is important to AlphaGo's playing
strength (or its scaling), or merely a minor tweak?


Thanks,

--
Petr Baudis
If you have good ideas, good data and fast computers,
you can do almost anything. -- Geoffrey Hinton

Olivier Teytaud

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Mar 9, 2016, 12:20:57 PM3/9/16
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To me the most surprising fact in this success is that Reinforce can be applied on such a huge neural net.
That's a huge number of parameters for a reinforcement learning algorithm - ok it's with a great computational power,
still I would not have guessed that reinforce could be applied on something that big..

I see a second very positive aspect, which is that many people in industry are more open-minded about neural nets
and AI today that 6 months ago - that's good for technology and technology is good for the world :-)
Olivier


--
=========================================================
Olivier Teytaud, INRIA TAO Research Fellow --- http://www.slideshare.net/teytaud
"Please stop quoting me on internet."___ Albert Einstein




valk...@phmp.se

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Mar 9, 2016, 12:53:17 PM3/9/16
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Hi!

I think the technique of hashing move pairs from the search tree and
reuse them in
the playouts if the context matches, could plausibly be the major
improvement of Alphago that
we witnessed today.

Another thing I noticed is that Alphago does not use any statistics from
the playouts other than wins and losses.
I think that is a improvement because it removes biases that might make
the program weak in certain situations.

On the other hand using the powerful move prediction accuracy from the
tree search and reuse that information in
playouts could really solve a lot of problems. In the way I see it
Alphago injects go knowledge into the playouts fro mthe search tree.
Traditional monte carlo programs would do the opposite. Add a lot of
knowledge to playouts and then try to squeeze
out as much statistics as possible.

Also the clever thing is that the playouts get fed knowledge from both
offline and online sources. When the search starts
the move ordering of the neural networks will help playouts with
suggestion of good shape moves. But as more and more
local situations are read out somewhere in the search tree, the playouts
will pick up more and more strong moves from the hashtable.

By the way I will start experiments with this soon in my new program!...
:-)

Best
Magnus Persson

_______________________________________________

wing

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Mar 9, 2016, 1:28:45 PM3/9/16
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In my opinion, the thing that programs do worst is ko.
Lee did not play any kos, except one minor irrelevant
one in the lower left. This game was so simple that
the program could accurately model the whole board.

If Lee wants to win, he needs to start 2 or 3
simultaneous kos.

Michael Wing

> Congratulations, AlphaGo and team. And by resignation! That's
> fantastic!
>
> Anyone know where the tipping point was? Did Sedol get the end game
> order just slightly off and AlphaGo took advantage? Or was their an
> earlier poor move by Sedol and/or surprising (and good) move by
> AlphaGo? I'm WAY too weak a player to even make stupid guesses. Any
> links to in depth analysis would be greatly appreciated!
>
> On Wed, Mar 9, 2016 at 1:46 AM, René van de Veerdonk
> <rene.vand...@gmail.com> wrote:
>
>> wow .. congrats to the AlphaGo team!!
>>
>> On Tue, Mar 8, 2016 at 11:43 PM, Hiroshi Yamashita
>> <y...@bd.mbn.or.jp> wrote:
>>
>>> AlphaGo won 1st game against Lee Sedol!
>>>
>>> Hiroshi Yamashita
>>>
>>> _______________________________________________
>>> Computer-go mailing list
>>> Compu...@computer-go.org

>>> http://computer-go.org/mailman/listinfo/computer-go [1]


>>
>> _______________________________________________
>> Computer-go mailing list
>> Compu...@computer-go.org

>> http://computer-go.org/mailman/listinfo/computer-go [1]
>
>
>
> Links:
> ------
> [1] http://computer-go.org/mailman/listinfo/computer-go

Hideki Kato

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Mar 9, 2016, 6:46:00 PM3/9/16
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Congratulations, Aja and David! Very remarkable win!

Pasky,

It's too early to conclude any, I think, because no records
of losing games have been published, ie., no weakpoints of
AlphaGo are open. I believe that the essential problems which
come from current MCTS (bottom-up) framework, such as solving
complex semeai's and double-ko's, aren't solved yet.

Hideki

Petr Baudis: <20160309171...@machine.or.cz>:
> Hi!

>

>

>

>

>etc.?

>

>

>

>

>

>

>

> Thanks,

>

>--

> Petr Baudis

>_______________________________________________

>Computer-go mailing list

>Compu...@computer-go.org

>http://computer-go.org/mailman/listinfo/computer-go
--
Hideki Kato <mailto:hideki...@ybb.ne.jp>

David Fotland

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Mar 10, 2016, 12:05:48 AM3/10/16
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I predicted Sedol would be shocked. I'm still routing for Sedol. From Scientific American interview...

Schaeffer and Fotland still predict Sedol will win the match. “I think the pro will win,” Fotland says, “But I think the pro will be shocked at how strong the program is.”

David Fotland

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Mar 10, 2016, 12:09:24 AM3/10/16
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Yes, I think the programs will have similar biases. In this game Sedol had some groups that were alive, but needed correct responses to stay alive. Even though the pro's stones won’t die, the playouts sometimes manage to kill them. This makes the program think it is more ahead than it actually is. AlphaGo should be much more accurate because it has a value network and can replay sequences from the mains search.

David

>
> I.e. is it fair to say that other computer programs will appreciate and
> understand the computer's moves better than the human's moves, so saying
> it is ahead is to be expected? (confirmation bias)
>
> Darren

Petr Baudis

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Mar 10, 2016, 5:39:35 AM3/10/16
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On Wed, Mar 09, 2016 at 09:05:48PM -0800, David Fotland wrote:
> I predicted Sedol would be shocked. I'm still routing for Sedol. From Scientific American interview...
>
> Schaeffer and Fotland still predict Sedol will win the match. “I think the pro will win,” Fotland says, “But I think the pro will be shocked at how strong the program is.”

In that case it's time for Lee Sedol to start working hard on turning
this match around, because AlphaGo won the second game too! :)

Petr Baudis

Petri Pitkanen

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Mar 10, 2016, 5:44:26 AM3/10/16
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This time I think game was tougher. Though too weak to judge. At the end sacrifice a fistfull stones does puzzle me, but again way too weak to analyze it.

It seem Lee Sedol is lucky if he wins a game

Petr Baudis

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Mar 10, 2016, 6:05:02 AM3/10/16
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In the press conference (https://youtu.be/l-GsfyVCBu0?t=5h40m00s), Lee
Sedol said that while he saw some questionable moves by AlphaGo in the
first game, he feels that the second game was a near-perfect play by
AlphaGo and he did not feel ahead at any point of the game.

--
Petr Baudis
If you have good ideas, good data and fast computers,
you can do almost anything. -- Geoffrey Hinton

Erik van der Werf

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Mar 10, 2016, 6:13:07 AM3/10/16
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Very impressive results so far!

If it's going to be a clean sweep, I hope we will get to see some handicap games :-)

Erik

"Ingo Althöfer"

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Mar 10, 2016, 6:40:39 AM3/10/16
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Hello,
 

Von: "Erik van der Werf" <erikvan...@gmail.com>
> Very impressive results so far!
 

indeed, almost unbelievable.


> If it's going to be a clean sweep, I hope we will get to see some handicap games :-)


I have another proposal, IF a clean sweep will happen:
There was an announcement three days ago by a Chinese group that
they are developing a strong go bot and want to challenge
No. 1 player Ke Jie (still in 2016).
The winner of that match might challenge AlphaGo.

Ingo.


http://senseis.xmp.net/?KeJie

Robert Jasiek

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Mar 10, 2016, 9:15:56 AM3/10/16
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On 10.03.2016 00:45, Hideki Kato wrote:
> such as solving complex semeai's and double-ko's, aren't solved yet.

To find out Alphago's weaknesses, there can be, in particular,

- this match
- careful analysis of its games
- Alphago playing on artificial problem positions incl. complex kos,
complex ko fights, complex sekis, complex semeais, complex endgames,
multiple connection problems, complex life and death problems (such as
Igo Hatsu Yoron 120) etc., and then theoretical analysis of such play
- semantic verification of the program code and interface
- theoretical study of the used theory and the generated dynamic data
(structures)

--
robert jasiek

Jim O'Flaherty

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Mar 10, 2016, 10:19:51 AM3/10/16
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I was surprised the Lee Sedol didn't take the game a bit further to probe AlphaGo and see how it responded to [...complex kos, complex ko fights, complex sekis, complex semeais, ..., multiple connection problems, complex life and death problems] as ammunition for his next game. I think he was so astonished at being put into a losing position, he wasn't mentally prepared to put himself in a student's role again, especially to an AI...which had clearly played much weaker games just 6 months ago. I'm hopeful Lee Sedol's team has been some meta-strategy sessions where, if he finds himself in a losing position in game two, he turns it into exploring a set of experiments to tease out some of the weaknesses to be better exploited in the remaining games.

Jim O'Flaherty

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Mar 10, 2016, 10:44:12 AM3/10/16
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I just realized that game 2 happened last night. ARGH! Stupid timezone error.

Darren Cook

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Mar 10, 2016, 10:48:45 AM3/10/16
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> I was surprised the Lee Sedol didn't take the game a bit further to probe
> AlphaGo and see how it responded to [...complex kos, complex ko fights,
> complex sekis, complex semeais, ..., multiple connection problems, complex
> life and death problems] as ammunition for his next game.

In fact in game 2, white 172 was described [1] as the losing move,
because it would have started a ko. (I suspect the game was already
lost, and that lesser MCTS programs would have managed correct play from
there, but it would still have been useful to see.)

(By the way, in game 2, black 43 and 45 were described as "a little
heavy". It did seem (to my weak eyes) to turn out poorly. I'm curious if
this was a real mistake by AlphaGo, or if it was already happy it was
leading, and this was the one it felt led to the safest win? I really
hope the AlphaGo team will publish what it thought its winrate was after
each move.)

Darren

[1]: https://gogameguru.com/alphago-races-ahead-2-0-lee-sedol/

Darren Cook

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Mar 10, 2016, 11:26:24 AM3/10/16
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> In fact in game 2, white 172 was described [1] as the losing move,
> because it would have started a ko. ...

"would have started a ko" --> "should have instead started a ko"

wing

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Mar 10, 2016, 1:13:08 PM3/10/16
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One question is whether Lee Sedol knows about these weaknesses.
Another question is whether he will exploit those weaknesses.
Lee has a very simple style of play that seems less ko-oriented
than other players, and this may play into the hands of Alpha.

Michael Wing

Lukas van de Wiel

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Mar 10, 2016, 1:38:14 PM3/10/16
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Congratz to AlphaGo, once more!
This is getting scary! :-)

Lukas

Marco Scheurer

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Mar 10, 2016, 1:43:59 PM3/10/16
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Congratulations indeed. 

Although I must admit I have mixed feelings about this, that it is Google, using enormous resources, that got there first. 

marco

Lukas van de Wiel

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Mar 10, 2016, 1:47:55 PM3/10/16
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The same here, with other people having built the foundations of go AIs, and going from neural networks to MCTS, and now back-ish again...
But that is how is how science works. Eventually these two wins are the reward of decades of culminated work by many people working on go AI. AlphaGo is the Cherry on the enormous cake.

Robert Jasiek

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Mar 10, 2016, 2:04:41 PM3/10/16
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On 10.03.2016 16:48, Darren Cook wrote:
> in game 2, black 43 and 45 were described as "a little
> heavy". It did seem (to my weak eyes) to turn out poorly. I'm curious if
> this was a real mistake by AlphaGo, or if it was already happy it was
> leading, and this was the one it felt led to the safest win?

In human terms, it was a combination of: limitation of the expansion
potential of the white left side, shinogi, sente and developing the
potential of the upper side including its center potential. Ugly and
marvellous strategy of simplifying the game (same: reduction of the
right side in sente) and creating a winning position by robbing White of
every option of creating significant new territory regions / expansions.

--
robert jasiek

Josef Moudrik

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Mar 10, 2016, 2:20:25 PM3/10/16
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Yes, but they are not some random cherry picking third party; have a look on the top authors of the paper - David Silver, Aja Huang, Chris Maddison..

Regards,
Josef


Dne čt 10. 3. 2016 19:47 uživatel Lukas van de Wiel <lukas.dr...@gmail.com> napsal:

Sorin Gherman

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Mar 10, 2016, 3:04:17 PM3/10/16
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I doubt that the human-perceived weaknesses in AlphaGo are really weaknesses - after the second game it seems more like AlphaGo has "everything under control".
Professional players will still find moves to criticize, but I want to see proof that any such move would change the fate of the game :-)

Sorin Gherman

Thomas Wolf

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Mar 10, 2016, 3:23:29 PM3/10/16
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My 2 cent:

Recent strong computer programs never loose by a few points. They are either
crashed before the end game starts (because when being clearly behind they play more
desperate and weaker moves because they mainly get negative feadback from
their search with mostly loosing branches and risky play gives them the only
winning sequences in their search) or they win by resignation or win
by a few points.

In other words, if a human player playing AlphaGo does not have a large
advantage already in the middle game, then AlphaGo will win whether it looks
like it or not (even to a 9p player like Michael Redmond was surprised
last night about the sudden gain of a number of points by AlphaGo in the
center in the end game: 4:42:10, 4:43:00, 4:43:28 in the video
https://gogameguru.com/alphago-2/)

In the middle and end game the reduced number of possible moves and the
precise and fast counting ability of computer programs are superior. In the
game commentary of the 1st game it was mentioned that Lee Sedol considers the
opening not to be his strongest part of the game. But with AlphaGo playing
top pro level even in the opening, a large advantage after the middle game
might simply be impossible to reach for a human.

About finding weakness:
In the absense of games of AlphaGo to study it might be interesting
to get a general idea by checking out the games where 7d Zen lost on KGS
recently.

Thomas

Petr Baudis

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Mar 10, 2016, 3:30:10 PM3/10/16
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On Thu, Mar 10, 2016 at 07:20:11PM +0000, Josef Moudrik wrote:
> Yes, but they are not some random cherry picking third party; have a look
> on the top authors of the paper - David Silver, Aja Huang, Chris Maddison..

Also, they aren't merely wrapping engineering around existing science
and putting existing things together, but invented several new methods
too. So, of course they are standing on the shoulders of giants, and
the massive computational resources of Google had been a lot of help,
but I'd say there is a fair amount of originality in the AlphaGo
research, scientifically.

Petr Baudis

uurtamo .

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Mar 10, 2016, 3:31:24 PM3/10/16
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Quick question - how, mechanically, is the opening being handled by alpha go and other recent very strong programs? Giant hand-entered or game-learned joseki books?

Thanks,

steve

Sorin Gherman

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Mar 10, 2016, 3:37:11 PM3/10/16
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From reading their article, AlphaGo makes no difference at all between start, middle and endgame.
Just like any other position, the empty (or almost empty, or almost full) board is just another game position in which it chooses (one of) the most promising moves in order to maximize her chance of winning.

Thomas Wolf

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Mar 10, 2016, 3:40:48 PM3/10/16
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But at the start of the game the statistical learning of infinitessimal
advantages of one opening move compared to another opening move is less
efficient than the learning done in the middle and end game.

uurtamo .

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Mar 10, 2016, 3:44:10 PM3/10/16
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If that's the case, then they should be able to give opinions on best first moves, best first two move combos, and best first three move combos. That'd be interesting to see. (Top 10 or so of each).

s.

Sorin Gherman

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Mar 10, 2016, 3:47:58 PM3/10/16
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For that reason I guess that AlphaGo opening style is mostly influenced by the net that is trained on strong human games, while as the game progresses the MC rollouts have more and more influence in choosing a move.
Is my understanding way off?

Olivier Teytaud

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Mar 10, 2016, 3:51:36 PM3/10/16
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The most surprising fact, to me, is that it's possible to apply "reinforce"
on such a large scale. Reinforce is not new, but even with millions of cores
I did not expect this to be possible. I would have assumed that reinforce would
just produce random noise when applied at such a scale :-)

--
=========================================================
Olivier Teytaud, olivier...@inria.fr, TAO, LRI, UMR 8623(CNRS - Univ. Paris-Sud),
bat 490 Univ. Paris-Sud F-91405 Orsay Cedex France http://www.slideshare.net/teytaud

Thomas Wolf

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Mar 10, 2016, 3:52:11 PM3/10/16
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With at most 2x361 or so different end scores but 10^{XXX} possible different
games, there are at least in the opening many moves with the same optimal
outcome. The difference between these moves is not the guaranteed score (they
are all optimal) but the difficulty to play optimal after that move. And the
human and computer strengths are rather different.

Jim O'Flaherty

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Mar 10, 2016, 6:48:37 PM3/10/16
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I think we are going to see a case of human professionals having drifted into a local optima in at least three areas:
  1) Early training around openings is so ingrained in their acquiring their skill (optimal neural plasticity window), there has been very little new discovery around the first third of the game with almost all professionals relying fairly strongly on the already time tested josekis - AIs can use reading to explore closer and closer to the start of a game using less and less automatic patterns thereby confusing humans who have memorized those patterns
  2) The middle of the board is so high in reading complexity, there has been little investment to figure out how to leverage it until mid game as it has been more expedient to focus on the corners and edges - AIs are going to get faster, better and deeper at reading through and then intentionally generating complexity
  3) As a human's cognition tires, the probability of reading errors rises non-linearly which increases the probability of late mid-game and end game errors - I think AlphaGo has already progressed pretty far in the end game

I'd consider these the three primary general vulnerabilities of human Go playing against any future AI. Given AlphaGo's training mechanism is actually search space exploration engine, it will slowly but surely explore and converge on more optimal play in all three of these domains significantly faster and cheaper than directly investing in and expending human cognition efforts; i.e. professionals studying to do the knowledge expansion and verification. And I think they will continue to optimize AlphaGo's algorithms in both human and self-play.

The window where humans are going to be able to fish out a win against AlphaGo is rapidly closing...and it may have already closed.


Other thoughts...

I think we are going to see some fascinating "discoveries" of errors in existing very old josekis. At some point, I think we will even see one or two new ones discovered by AIs or by humans exploiting AIs. We are going to see some new center oriented fighting based on vastly more complex move sequences which will result in an substantial increase in resignations at the professional level against each other. 

Said a slightly different way...even if Lee Sedol figures how how to get a lead in a game during the opening, AlphaGo will just continue to elevate the board complexity with each move until it is just beyond its opponent's reading ability while staying well within it's own reading ability constraints. IOW, complexity is now an AIs advantage. AlphaGo doesn't have the human frailty of being nervous of a possible future mistake and then altering its priorities by pushing winning by a higher margin as a buffer against said future reading complexity mistake. IOW, AlphaGo is regulated by it's algorithm's prioritizing the probability of win higher than the amount of margin by which it could buffer for a win. What seems like a weakness is turning out to be one hell of a strength.

Add to the fact that this kind of behavior by AlphaGo is denying it's opponent critical information about the state of the game which is more readily available in human-vs-human games; i.e. AlphaGo's will continue to converge towards calmer and calmer play in the face of chaotic play. And the calmer it becomes, the less "weakness surface area" it will have for a human to exploit in attempting a win.

This is utterly fascinating to get to witness. I sure wish Don Daily was still here to get to enjoy this.

Brian Sheppard

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Mar 10, 2016, 7:55:17 PM3/10/16
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Amen to Don Dailey. He would be so proud.

terry mcintyre

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Mar 10, 2016, 9:45:02 PM3/10/16
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According to the paper, AlphaGo did not use an opening book at all, in the version which played Fan Hui.

Hypothetically, they could have grafted one on. I read a report that the first move in game 2 vs. Lee Sedol took only seconds. On the other hand, it's first move in game 1 took a longer while. We can only speculate. 


Sent from Yahoo Mail for iPad

Seo Sanghyeon

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Mar 10, 2016, 10:50:12 PM3/10/16
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2016-03-11 11:42 GMT+09:00 terry mcintyre <terrym...@yahoo.com>:
> Hypothetically, they could have grafted one on. I read a report that the
> first move in game 2 vs. Lee Sedol took only seconds. On the other hand,
> it's first move in game 1 took a longer while. We can only speculate.

This is easy to explain. AlphaGo was white (second to play) in game 1,
and black (first to play) in game 2. You can precalculate a move if you are
first to play. Harder to do that if you are second.

--
Seo Sanghyeon

uurtamo .

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Mar 11, 2016, 12:58:17 AM3/11/16
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Not to put too fine a point on it, but there's not very many two or three-move combos on an empty board. As staggering as it is, I'm inclined to believe without further evidence that there's no book or just a very light book.

s.

David Fotland

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Mar 11, 2016, 1:24:21 AM3/11/16
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He was already in Byo-yomi, so perhaps he didn’t have an accurate count. This might explain why he looked upset at move 175. He might have realized his mistake.

David

> -----Original Message-----
> From: Computer-go [mailto:computer-...@computer-go.org] On Behalf
> Of Darren Cook
> Sent: Thursday, March 10, 2016 8:26 AM
> To: compu...@computer-go.org
> Subject: Re: [Computer-go] Finding Alphago's Weaknesses
>

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