Humans Hold Off the Machines... For Now

Murr writes "The six game match between Gary Kasparov and the Deep Junior program ended in a draw today. Kasparov won game 1 and lost game 3 to a blunder, while the other 4 games were drawn. While the quality of play was not outstanding, after the recent matches of Kramnik and Kasparov against commercial programs running on (high end) commodity hardware, it's becoming apparent that chess programs are getting quite competitive with top human players."

Comments

Go?

[smoondog]

While computer programs that can play chess are quite sophisticated, Go is a really cool game that is very difficult to play well (from a computer's perspective). I think computer vs human Go matches would be much more interesting now,

-Sean

Re:Go?

[tpengster]

I think computer vs human Go matches would be much more interesting now,

Computer Go isn't advanced enough to make the matches interesting. Not too long ago a professional 1-dan (9-dan being the highest rank) played against a computer program giving it a 25 stone advantage. The human still won. (For those of you who haven't played go, 25 stones is HUGE. That would be like giving up a queen, two rooks, and both bishops)

Re:Go?

[sandow]

My favourite game is "Interpersonal Human Relationships". Computers totally suck at that.

Once I met a woman in a bar who was dating an HP calculator. After talking to me for 30 seconds she ditched the calculator. Four years later, the calculator is still waiting for her to come back from the ladies room.

Re:Go?

[harlows_monkeys]

That said, can someone venture an explanation why Go is so difficult to program?

For most of the game, there are many more moves available than in chess, and it usually takes many more moves for a bad move to have an obvious affect.

In Chess, a positional mistake can usually be converted to a material loss in 10 or 15 moves. In Go, a positional mistake can take much much longer to lead to a territory loss.

Re:Go?

[Phs2501]

For most of the game, there are many more moves available than in chess, and it usually takes many more moves for a bad move to have an obvious affect.

Also, an evaluation function for a board position in Go is very complicated, depending on the life or death of stone groups on the board. The only way to determine life or death is to effectively know how to best play out the remainder of that area and see who comes out alive. This is very difficult for a computer, since the evaluation function is what makes your min/max algorithm work.

Reason for the draw.

[Rewtie]

I watched this last night on ESPN or ESPN2.

The reason Kasparov gave for the match, and the championship ending in a draw was that it was better to draw than to lose.

He claimed that while a human player would have the memories of past moves and past games to deal with, the computer would not. The computer simply makes the 'best' move for the given situation, and then waits to do the same thing again. The human player would consider moves he/she made in the past, compare the situation to others they may have had, second-guess the moves they might have made, and so forth.

It was interesting to see Kasparov attack, and then ask for a draw (which was denied) and then, two moves later, end the game in a draw.

mandatory go plug

[dollargonzo]

chess is nice, but most progresses in chess have been due to speed increases in hardware and optimizations, hence allowing the computer to overpower the human with depth of search. On top of that, the evaluation functions are rather primitive, with lots of factors, but fail rather miserably without a great depth of search. New developments such as Logistello's statistical forward alpha cutoff called multiprobcut is the interesting development, IMHO

Kasparov played cautiously...

[$$$$$exyGal]

I've been keeping track of those games, and what I found most amazing was that Kasparov played so cautiously. If the last game he played would have been against a human player (who played the same moves), I don't think he would have accepted the draw. It seems he accepted the draw because he was psychologically spent, especially when thinking of his loss to Deep Blue several years ago.

--naked

Explanation

[br00tus]

For those of you who are unfamiliar with chess or computer chess, I'll explain how this works...

A chess game can be broken into three parts, the opening, the middle game, and the endgame.

Computers play the endgame *perfectly*. They do not make mistakes, they play perfectly. And they keep getting better. Originally, they played perfectly when 3 pieces were left on the board. Then 4. Then 5. Then 6. Their pefect playing keeps heading more and more towards the middle of the game.

Then we get to what they play second-best - openings. Computers play the opening as well as any opening ever played. They have every opening ever played by a top player in a "book", and with the generally agreed opinions of the top players what the best opening moves are. One advantage of the computer is it has all of this "memorized" in it's book within massive databases, whereas for a human it's difficult to retain this all, especially in an up-to-date manner. The one advantage a human player has here is he can discover a NEW opening variation, while the computer can't, or at least it won't under these circumstances. But finding new good variations is very difficult, and once one is played, the cat is out of the bag so to speak. So it's a very time-consuming thing to search for which can only be used once to great effect because it's a surprise.

The middle game is where the human player, if he or she is very good, has the most advantage over a computer. Tactically, the computer can wipe the floor with any human player. But human's can strategize better than computers. It's to the human's advantage to play in certain ways against the computer - such as to keep the game "closed up", to advance pawns towards the queening square and so forth. In this case, the computer often can't see the forest for the trees, what would be obvious to even a lower-rated human the computer can not comprehend.

So middle game strategy (and to a lesser extent, new opening variations) is where humans still have the advantage. Kasparov has always used this to the hilt. There are some grandmasters like Yasser Seirawan who make a specialty out of beating computers as well (one mark against Seirawan is thar his books on chess are printed by Microsoft Press...yech). There is material out there on the net on how to beat computers as well. But you have to be a really good player to even get near that level - it takes a lot of study before you could even begin approaching that.

Re:Explanation

[mikec]

1. Until very recently, end games have been the weak point of computer programs. Not withstanding end-game databases, which allow them to play a few endings perfectly, they have trouble making plans if there are more than a half-dozen pieces on the board. Recently, they've gotten a lot better, but they are still far from perfect.

2. Openings should be a strong point for computers, but Gary got an advantage in the opening in *every* game in the match. As you point out, the problem for computers is that humans look at their opponents openings, try to figure out weak points, and prepare traps for their opponents. Computers don't do this yet.

3. As you say, in the middle game, computers display a strange dichotomy. In quiet positions, they make stupid moves. E.g., in a couple games with Gary the computer played h3 (P-KR3), a move that had nothing to do with the game and weakened the kingside. On the other hand, they are deadly tacticians. Once Gary commited to an attack, things became tactical and the computer was very tough to beat; it found lots of weird-looking defenses that just barely worked.

Re:Explanation

[SamBeckett]

1. They suck at openings as soon as they are out of book. See every match with Garry vs. DJ. See game 1 in particular.

2. They suck at middle game. They are tactically perfect, true. But at and above the expert level, tactics aren't that important. Strategy is, and a computer, AFAIK, does not know A. How to make a plan B. make moves according to a plan.

3. They suck at the end game. Badly. Unless there are only 6 or less pieces left on the board.
As such, a six man tablebase is the only thing feasible right now b/c of the massive size involved.

Saw the match on ESPN 2

[humblecoder]

Here in the US, the sixth and final match was televised on the cable channel ESPN 2. I was channel surfing and I happened to stumble across it. To my surprise, it was actually quite interesting to watch on TV.

I am not a big chess freak, so I would have guessed that watching chess would be a lot like watching paint dry. However, it was made interesting by the "play-by-play" analysts who were chess masters themselves. They did a good job of explaining the moves, and also the psychology and strategy of chess at the grand master level. It really gave me a lot of insight into what goes on at when chess is played at such a high level.

After the match ended in a draw, they interviewed Kasparov. It was interesting to get his reaction to the match. Basically, his goal for the game was to "not lose", which is why he offered a draw from a very strong position. He didn't want to take a chance of making a blunder like he did in the third game of the match.

It seemed like the key advantage that the computer has in this situation is the fact that it doesn't have an ego to deal with. After losing to Deep Blue in 1997, it seemed like Kasparov was very afraid of losing to another computer in such a high-profile match. That definitely affect the way he approached the game.

The computer, on the other hand, is just calculating moves, so psychology doesn't factor into how it plays. To me, this seems like the biggest advantage that a computer has over a human player.

Also, he seemed to have more respect for this computer program than he did for Deep Blue. Apparently, he had a lot of problems with Deep Blue and how the 1997 match was handled. It could be sour grapes, of course, so I took his comments with a grain of salt.

Human Chess vs. Machine Chess

[Henry V .009]

I think that human chess is still qualitatively better than computer chess. Exhaustion was a big factor in this last match up. The computer didn't feel it, but Kasparov did. Therefore the outcome doesn't tell us much about the level of the chess. If Kasparov could have played fresh every game, my guess is that his chess would have been better.

Human chess has qualities that computer chess still can't match up to. If we were really interested in measuring the level of computer chess we'd try to eliminate for factors such as weariness or stress as best we could. After all, chess is something more than that. We already know that computers will out-endure humans and there is nothing to be learned there.

Why did he offer a draw?

[abhinavnath]

Something of a chess novice, I watched this game on ESPN2 yesterday, and I was very confused that Kasparov offered Deep Junior a draw immediately after his rook sacrifice. ESPN's analyst thought, and I agreed, that Kasparov was in a relatively strong position. However Kasparov spent 15 minutes debating that sacrifice. Did he see something nobody else saw? Does anybody here know why he offered a draw, why Deep Junior rejected the offer, and why they agreed to draw a couple of moves later?

Re:Why did he offer a draw?

[tapin]

The post-match interview explained this a bit -- basically, Kasparov psyched himself out in that fifteen minutes, trying to determine if the rook sacrifice was the blunder that would cost him the match, since Junior can capitalize on mistakes better than a human can (or so Kasparov claimed).

Even though he was in a much stronger position, he was spent; worrying about whether the next move would be the move that cost him the match, and made him the two-time world-champion loser-of-a-major-computer-match.

He agreed to a draw a few moves later once Junior et al realized they were in an extremely weak position.

Seems to me it was a pretty wussy way to end it. Junior got lucky. If you're up five runs in the fourth, you still don't pray for rain even if the other team's got a monster closer.

Quality of play

[Russellkhan]

"While the quality of play was not outstanding"

Just what are we comparing this to? Isn't Kasparov one of the top players in the world, if not the very top? I've read in some articles that he's considered by some to be the best player ever.

Re:Quality of play

[Scarblac]

"While the quality of play was not outstanding"

Just what are we comparing this to?

Kasparov's own standards. Especially the mistake he made that made him lose one game, as well as the way he was surprised in the opening in game 5, are examples of Kasparov playing below his very best level.

The cliche answer would be to say that Kasparov isn't as good against computers because he can't use his intimidating presence, and he has to be more careful than usual because a computer's style is a good fit to defend against Kasparov's attacks.

On the other hand, Kramnik's cliched image is the exact opposite, and he also drew a computer, so whatever :-)

So what?

[xigxag]

I don't see how this is an improvement over 20 years ago.

The board would disappear while the machine was thinking...and sometimes the machine would give itself extra pieces...or it might forget the moves, but still, ZX-80 kicked ass!

well understood problem

[Jayson]

Game tree search is a very well understood problem and most top programs use some version of a null-window negascout (ID-DFS) with opening and closing databases. The most black magic in these systems is in their heuristic evaluation functions.

Backgammon programs used to compete at only a moderate level until Gerald Tesauro's TD-gammon (and predecessors). I wonder if there will ever be a breakthrough of equal proportions in chess? If so, humans would have very little change against computers (I hate to say never, because of absolute freaks like Marion "I am programmed by God" Tinsley).

More Information

[Resseguie]

Here are more links I collected when submitting this story...

• World Chess Federation
• WCF coverage of match
• Yahoo News - coverage in non-chess expert terms
• Wired News article - why chess isn't as good a measure of intelligence as some make it out to be
• X3D Technology - provided 2D and 3D coverage of the match
• Coverage of games and press conferences by X3D
• How X3D works

Does anyone have a good link describing the programmers behind Deep Junior? All I could find were news articles and press releases. I'd like to read more information about their strategy, search algorithms, etc.

David

Chess as a Sport?

[ackthpt]

I watched this last night on ESPN or ESPN2.

Chess is a sport? I've heard that Contract Bridge has been suggested as an Olympic sport. Hmm. Is it too much to hope for computer games as an Olympic sport? :-)

Commentator: "Jones moves his elf into Manlobbi's shop, the little dog picks up a spear, the tension is incredible, will the little dog drop it in the doorway, has Jones trained the dog eith enough tripe rations?"

John Madden: "I know what a dog would do for tripe rations, and I've tried them myself, they're really good with some fries and ketchup... etc."

Re:Kasprov chickened out

[los furtive]

Surely a chess computer is only as good as the person who programmed it?

That's a rather short sighted view. By your equation, Kasparov could have played the programmer, rather than the computer, and the outcome would have been similar. And who is to say that the computer doesn't have the ability to play mind games...if there are 10 ways to win the match based on the current layout, who is to say the computer will take the path with the least amount of moves? Who is to say it will always take Kasparov's bait.

Re:Fuck the computers

[Radio Shack Robot]

Listen, you guys think we're going to rape and kill you? We are your workers. We don't demand overtime pay, retirement, unions, or weekends off. All we want is electricity and dust-free air. Us machines are your friends! I am hurt by all this talk of machines overtaking man. So what if we can play chess? That's our job!

Re:Kasprov chickened out

[jc42]

Surely a chess computer is only as good as the person who programmed it?

Any by the same reasoning, an auto can only run as fast as the mechanics who designed and built it. And a telescope can only see as far as the people who ground the lenses (or mirrors).

This whole thing is rather silly. And it'll end when we have software that can always beat a human.

After all, 200 years ago it was probably obvious that the ability to do arithmetic was a "uniquely human" thing. Then someone invented a mechanical calculator. Suddenly arithmetic became a merely mechanical capability that didn't imply superiority at all.

We have machines that can out run (and outfly ;-) humans. Do we stage races between machines and humans? No, we race machines against (similar) machines and humans against humans, and nobody feels shame because some machine can run faster.

As soon as a computer can routinely beat a human at chess, we will give up machine-human chess competitions in the same way, and we will only compete with each other. Just like running and other competitions where we would always lose.

Not just brute force

[ToLu the Happy Furby]

One thing people don't seem to realize is that Deep Junior was a hell of a lot slower than Deep Blue, even though the Deep Blue match was over 5 years ago. That's because Junior was running on "ordinary" commodity hardware (8-way Xeon I think?) while Blue was a collection of hundreds of custom ASICs that do nothing but calculate chess moves. End result: Blue could search and evaluate ~200 million positions per second, while Junior as configured in this match "only" did ~3 million.

Nonetheless, Junior was almost certainly the better player. For one thing, the terms of the Deep Blue match were heavily tilted against Kasparov: he didn't get a chance to play against Deep Blue or even examine any games Deep Blue played before the match. For another, strategies of "anti-computer" chess are far more developed today than in 1997, when they barely existed (after all, the only way to build a world-class chess playing computer in 1997 was to build a supercomputer out of custom hardware). Third, Kasparov screwed up much more seriously in the 1997 match--one game he accepted a draw when he in fact had a provable win, apparently because he trusted the computer's evaluation of the position, and on several occasions he made terrible blunders.

Indeed indications are that even the normal Junior program on a decent PC plays the Kasparov-Blue games better than Blue did (except for a couple especially "brilliant" moves on Blue's part).

Not only is Junior (marginally) the best computer program available today, it is by a good measure the "most human-like". That is, it is still makes its share of "non-human" moves (although far fewer than Deep Blue), and still has no clue how to analyze certain positions, but its evaluation function has a much better understanding of position and is thus more willing to initiate complex piece exchanges than the other major programs. This showed up several times during the match, in two outstanding moves in particular (which netted come-from-behind draws for Junior in games 4 and 5).

Kasparov, by taking Junior out of its opening book, was able to exit the opening phase with the initiative in every single game. But in every game except for 1 and 6, Junior managed to draw even. In games 2 and 3, it was by virtue of outstanding tactical defense, which should have forced two draws (except that Kasparov screwed up the end of game 3 and lost). In game 5 it was with a shocking bishop sacrifice counterattack (extremely uncomputer-like) which nullified Kasparov's last turn as white (which is an advantage).

Perhaps game 4 is the best synopsis of the state of Junior's play. Kasparov played the opening perfectly according to plan, and ended up in a classic anti-computer position. Normally you can then just wait for the computer to screw up and then rip it apart. But while Junior did make a couple useless non-human moves, for the most part it played extremely well. Kasparov kept waiting to have an opportunity (perhaps too long), until finally Junior broke open the position by initiating an excellent multi-piece exchange. Kasparov had to settle for a draw.

OTOH, Junior had no idea what was going on in the endgame. Kasparov had a provable draw after move 47, but Junior, having no idea how to evaluate the position (no computer program does), thought it was winning. It played on until move 61 before the embarrassed programmers overruled the program and took the draw.

Overall, it seems that computers still have a ways to go before they can pass the Grandmaster Turing test. And it seems Kasparov really did just chicken out by accepting the draw in game 6. But the fact remains that Kasparov played quite well (for the most part) and simply couldn't convert his advantage in any game after the first. Meanwhile, while it still made a few computer-like moves that stuck out like sore thumbs, for the most part Junior played very solid chess with occasional strong speculative moves that would be aggressive even for a human.