

Why the Chess Computer Deep Blue Played Like a Human - dnetesn
http://nautil.us/issue/18/genius/why-the-chess-computer-deep-blue-played-like-a-human

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hackinthebochs
The interesting thing about the Monte Carlo approach is that it depends on the
property that a randomly chosen move (or branch) can be representative of a
similar set of moves. In a game like Go this is true because there are many
sequences of moves that end up in exactly the same game state, and slight
variations of board position have the same utility. But in chess, slight
variations in every board position will have huge impact on the outcome of the
came. Raw calculation is a necessary component of strong play and intuition is
much less useful.

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slyall
Chess engines that use Monte Carlo don't make moves completely at random, they
use a small search depth when playing through the games to ensure that fairly
good moves are mode.

A short writeup here of it in practice (images broken unfortunately) here:

[http://en.chessbase.com/post/rybka-s-monte-carlo-
analysis](http://en.chessbase.com/post/rybka-s-monte-carlo-analysis)

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j00lz
Also worth noting that IBM stock price increased by $2Billion after defeating
Kasparov. So they have had everything to gain by beating him at whatever cost.

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3pt14159
Stock prices going up have nothing to do with the incentives of companies and
everything to do with the availability of information.

It'd be like a gumball machine trying to make itself more valuable. Just sell
more gumballs at a hirer price.

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j00lz
The incentive of public companies is everything to do with stockprice, as it
is the primary metric to rate the performance of a company? What does
information availability have anything to do with the value of a company?

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DMac87
It is fascinating to compare & contrast chess, Go, and backgammon, and how
quite different approaches are needed to program in each. For chess, 'pure
calculation' is most effective, while the author suggests MC is good for Go &
others. In backgammon, TD-gammon used a rather naive neural net approach and
trained itself, optimizing its own play over time! It is also interesting how
computers' success in these areas feeds back into how humans play the game (at
least in backgammon and chess opening strategy).

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Jun8
It's been remarked that backgammon is man's struggle against change, chess is
his struggle against another man, and Go is his struggle against himself.
While there's some artistic license (a good backgammon player will crush a
mediocre one in the long run) this comment does provide some interesting
cultural.

And there's also a _Shibumi_ quote I like: "Go is to Western chess what
philosophy is to double-entry accounting." This book was the first time I
heard about Go.

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swang
I've always been curious if what Kasparov calls, "human intuition" by Deep
Blue was merely Deep Blue being able to search more plies than any computer
could before it.

Also, not sure if it was fair for IBM engineers to change Deep Blue code
during the actual match. Because now you are actually playing against both
humans and machines. It would have been a huge blow for IBM if the machine
they've spent to long working on couldn't beat Kasparov.

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cheepin
I think IBM did several things that weren't fair to Kasparov, changing the
code between games being only one. I would actually say the more important
piece was that he wasn't able to practice against Deep Blue or study its games
against other players.

We tend to romanticize Chess as being a hyper-intellectual game where if you
are good enough, you should be able to beat anyone worse than you 100% of the
time. The truth is a lot more subtle. Chess is indeed a perfect-information
game, so there isn't _true_ luck involved, but due to the fact that we can't
just search the entire game tree, we introduce several elements of
uncertainty. Namely, that past a certain point, you must play your opponent as
much as the board. Players (and AIs) naturally have certain strengths and
weaknesses, and the ability to steer the game into positions that play to your
strengths and opponents weaknesses is often just as important as your overall
game strength. Some of the best players in the world are known for how
intensely they prepare for specific opponents.

In short, Deep Blue had 'preparation' against Kasparov from all his game
histories, while Kasparov did not have the same benefit. While switching the
code could be considered analogous to switching to a whole new opponent
(though likely only a small change in practice), the overall unpreparedness
was probably the larger factor. In my opinion Kasparov was a stronger player
than 1997 Deep Blue, but this asymmetry probably cost him the series.

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nobodysfool
In short, Deep Blue had 'preparation' against Kasparov from all his game
histories, while Kasparov did not have the same benefit.

Kasparov had the benefit of playing all those games as well. ;)

As for your allegations of unfairness, code tweaks were allowed between games.
It was part of the rules. Just not during games. And if Kasparov didn't think
the rules were fair he could have declined the match.

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nemothekid
>Kasparov had the benefit of playing all those games as well. ;)

You missed his point, its not about practice. The top chess players often
study their opponents to understand what types of moves they make and in what
situations they make those moves. If Kasparov were to play any other player in
highly ranked matched both players would go and study their opponents move to
get an insight in the way they think.

The "unfairness" in the Deep Blue match (or what made the Deep Blue match
unlike other top-level play Chess), is that Deep Blue had a deep understanding
of Kasparov's moves, but Kasparov had no information about Deep Blue's moves.
And to make matters worse, any information he had built up in the previous
games were erased once they tweaked the code.

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ganzuul
I thought he walked out on the match because he was upset that the computer
DIDN'T behave like a human. Huh. Weird, these narratives.

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jpablo
He didn't walk out. He played all six games in the match and lost the match in
the last game after he played a opening that was know as losing by everyone
after a piece sacrifice (it was speculated that Kasparov was gambling that
deep blue wouldn't make the sacrifice and then he will have the upper hand).

Deep blue played pretty much "like a machine" except for a few moves that
where considered very human because they hold very long term advantages.

After the match Kasparov hinted that IBM must have cheated, of course now a
days a machine running in a off the shell desktop machine will surely beat the
current world champion in a match, so Kasparov was just being a sore loser at
the time.

~~~
casion
He felt that the engineers intervened DURING the games, and obviously did not
feel that intervention between games was reasonable either. The former was
disallowed, and the latter was taken advantage of more than Kasparov thought
it would be.

He wasn't being a sore loser and there was a reasonable amount of agreement
among other chess professionals (engine authors and players) that his claims
were true.

Keep in mind as well that when he asked for a rematch with more stringent
scrutiny in place, IBM declined and nearly immediately dismantled Deep Blue.

The unfortunate thing is that kasparov would ALWAYS have looked like a 'sore
loser' unless IBM decided to implicate themselves of wrongdoing. Kasparov
being silent also does a disservice to the community, particularly since he
was neither the first or only person to point out the inconsistencies in Deep
Blue's play.

Keep in mind as well that the 'real circumstances' make it so both parties
responses were rationally founded within the context of the available
information at the time.

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V-2
We will never know for sure. If I was IBM, after the cheating accusations I'd
probably refuse a rematch, too, even if I didn't cheat.

Why? Because unlike before, it would generate bad publicity for me now (the
reason for a rematch would keep on being mentioned), and God forbid if
ubermotivated Kasparov managed to triumph this time, under tighter scrutiny.
Now the public is convinced that I cheated before... The atmosphere was
spoiled and they had nothing to win in terms of PR anymore, really.

It was only reasonable to swipe it under the rug and move on. Obviously it
does not mean that they were clean. Dropping Deep Blue is not an indicator of
either in and of itself, because it makes perfect sense in either case. We
just can't know.

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casion
My point about the rematch is that it made more reasonable to the chess
community to believe Kasparov's claims.

From IBM's perspective, it made sense as you pointed out. From Kasparov's
perspective, it also made sense for them to decline , but for a wholly
different reason.

It really was just a sad situation where nobody could come out on top except
for IBM. Even if they DID cheat, they were the only ones who were capable of
proving that. IBM simply outsmarted Kasparov outside the game.

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sitkack
Afaik, I thought the engineers running the machine were reprogramming during
the game to handle changes in Kasparov's technique. Please someone with more
knowledge chime in, but from my memory it was more like he was competing
against computationally augmented human opponent. He wasn't beaten by a
computer, he was beaten by a team of engineers using a computer.

some corroboration on
[http://en.wikipedia.org/wiki/Deep_Blue_(chess_computer)](http://en.wikipedia.org/wiki/Deep_Blue_\(chess_computer\))

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DMac87
Not reprogramming during any game, but during the match (between games). You
can argue about how much influence this has, in my mind though he was beaten
by highly similar variants of a computer program (not quite a fixed concept,
but not adjusted too much during the match).

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Arnor
Kasparov also complained that he was never allowed to see any logs or previous
games by Deep Blue ahead of the match. If he was playing another GM, there
would have been hundreds of games available where he could get a feeling for
the player's preferences. Preparing for such a high level match necessarily
requires such preparations.

~~~
jacquesm
He should have made his participation conditional on being shown previous
games. I'm pretty sure everybody outside of IBM would have considered that
fair.

IBM reminds me of a kid at school that would play everybody that was playing
chess up until the point where he'd win _once_ against them. Then he'd run off
and spout to everybody that he was now better than 'x'. The rematch offer was
pretty lame after the cheating accusations, they should have addressed those
first. No rematch given those conditions, no prior data -> no fair victory.

If IBM wanted to do this fairly they'd give Kasparov at least as much data on
Deep Blue as they had on Kasparov.

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aaron695
By Nate Silver's FiveThirtyEight a short doco

[http://fivethirtyeight.com/features/the-man-vs-the-
machine-f...](http://fivethirtyeight.com/features/the-man-vs-the-machine-
fivethirtyeight-films-signals/) (17mins)

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johnaspden
Fun article, but does anyone else find the damned banner at the top of the
page infuriatingly distracting? And is there a way to make it go away?

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johnaspden
Ah, in firefox, right click -> inspect element, find 'position fixed', and
untick it. Page behaves....

So is there any way to do this automatically whenever websites do this sort of
thing?

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ganzuul
Stylish/Userstyles might let you script at it easily, but there doesn't seem
to be a dedicated app.

