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Computer Cracks 5x5 Go
gustgr writes "The American Go Association is reporting that Go for the 5x5 board has been solved by the computer program MIGOS, reports the program's creator, Erik Van Der Werk, a professor at the University of Maastricht in Holland. At about a quarter of the full-board version, 5x5 go is miniscule, similar in scale to "solving" 2X2 chess. The fact that a programmer would even consider this a noteworthy challenge is itself a remarkable testament to the game's complexity. Van Der Werk's approach is described in detail in an
article at the Netherlands Organization for Scientific Research (NOSR)."
The doctoral thesis was defended on 27 January 2005
Maybe the results came out just now.
5x5 is 1/4 the size of 19x19??? More like 1/14th.
The way that chess games work is they check n ammount of moves into the future. With each iteration into the next move it splits off into a massive tree of moves. As an example, the first iteration has 10 potential moves, the next has 100 and the next has 1,000 With Go as an example there may be 100 potential moves on the first iteration and then 10,000 and then 10,000,000 The number of potential moves grows way faster then in chess.
Check out this for a decent comparison between chess and go for those of you who have been missing out.
Also, dig my sig biotches.
Direct away from face when opening.
For another thing, go is spectacularly more complex than chess. The very best go programs are competition only for weak amateurs. There's an archived NYT article that summarizes the problems reasonably well.
Although the standard go board is 19x19 intersections, the game scales, unlike chess. Things you learn on a small board are sometimes applicable to larger ones. A 5x5 is usually not interesting for human play; most consider 9x9 the minimum size for a worthwhile game. This means that a computer has been programmed to force a guaranteed win at a smaller size, and hopefully paves the way for further development and understanding.
This isn't as much "normalization" as it is "don't take so many drugs when you're designing tables."
A full-size Go board is 19x19, but you're right in your main point.
I found the meaning of life the other day, but I had write-only access.
AFAIK, the current state of the art of Go on computers is Goemate and Go4++.
GNU Go is actively developed, but it still does not match commercial Go software, ranking 1-2 stones weaker. It is rated from 8 to 9 kru, which is a weak amateur.
Computers have thus far not been too great at cracking go via the usual searching algorithms, as it has a high branching factor - starting at 361, much higher than chess! It is only recently that Go programs have even begun to achieve low levels of competence. Besides the limited searching and pattern recognition of current software, future programs may improve by decomposing Go into 'subgames', allowing it to be more readily attacked.
A 5x5 go board has only 847,288,609,443 possible game states, even including impossible boards. Assuming the relatively tame pace of scoring 100,000 boards per second towards completion, which on a board of that size is trivial, this solution takes a simple brute-force time of 98 days. That solution space can be cut down by almost two orders of magnitude with simple reflection and rotation tricks, implying a realtime tree search space of about a day and a half.
Given that my full board scorer moves faster than that, and given that the university probably has more than one PC to work with, I wonder how it is that anyone can justify this as something larger than a publicity stunt, especially given that none of go's emergent structures even fit onto a 5x5 board.
This is horseshit, in short. Mod story down.
StoneCypher is Full of BS
The canonical game (7 columns, 6 rows) has been solved.
And real Go can be played at KGS.
"Never attribute to malice that which can be adequately explained by stupidity." -- Hanlon's Razor
The other posters are correct. If you really RTFFA, you'll find that it was solved October 20th 2002, well over two years ago. Even the link you provide only mentions the corresponding doctoral thesis beind defended recently (January 27th 2005). Perhaps you should RYOFL (Read Your Own Frelling Links).
It seems you know next to nothing about go. Stronger players give weaker players a handicap. The handicap is a number of stones placed on the board before as the game begins. The number of stones is simply the difference is ranking. Beginners start at around 13 Kyu, progressing to 1 Kyu. From 1 Kyu, progress is to 1 Dan up to 9 Dan. When a 4 Dan plays a 1 Kyu, the 1 Kyu should get a 4 stone handicap. (I know about the professional Dan scale, and I'm ignoring it).
If two folks who do not know their ratings play, the handicap can be determined after the first game by dividing the winning margin by 10. Now was that hard?
A handicap game of go is a lot more interesting than a game of chess between a master and a class A player.
All this assumes that you are serious about your games and are willing to work on getting good. If all you want to do is kill time, go still has simpler rules, and you can use the set to play gomoku.
To put this into even more perspective
..., 9 dan.
In go, players can be given a rank on how strong they are compared to others. It's a fairly simple method.
Everyone starts out at about 30 kyu. As they get stronger, their kyu number decreases till it gets to 1 kyu. At which point starts a new number system that goes upward, starting at 1 dan and goes to 9 dan.
So..
30 Kyu, is weaker then a 29 kyu,... 2 kyu, 1 kyu, 1 dan, 2 dan,
Now that is for amateur rankings. There is a professional ranking system that starts at 1 dan pro and goes to 9 dan pro. I have heard that a 1 dan pro is roughly the same strength as a 7 dan amateur.
There is a handicap system where if you take the rankings of two players and subtract them, it determines the number of handicap stones given to the weaker player. Thus a 10 kyu playing against an 8 kyu, the 10 kyu player gets to play first by placing 2 stones on the board (one set of rules allows black to place the stones anywhere on the board, another set of rules, the stones must be played at specific spots). The rule of thumb is that each handicap stone is worth about 10 points. Another rule of thumb is that each handicap stone "erases" one mistake by the weaker player.
Normally one doesn't play with more then a 9 stone handicap. Mainly because beyond 9 stones, black really isn't "learning" much
To prevent ties, a half point is awarded to white in handicap games, in an even game (where both players are of equal strength), white is given 6.5 points (this has been changing around some -- depending on the rules you are playing with).
Usually after the 1st game or so a 30 kyu player learns enough to drop to around 28 kyu or there abouts.
I have heard that the amount of time and study to go from a 10 kyu to a 1 kyu rank is about the same as going from a 1 dan to a 2 dan.
A game between two weaker players can result in scores of anywhere from just a few points to 100's of points going to the winner. As one gets stronger, the wins are usually only a few points, or someone resigns.
I have seen strong dan and pro players when playing weaker players their goal is to try to get the score within a half point (always in their favor).
In Go, the game really doesn't start to get interesting till about 30 to 50 moves into the game (in chess, the game is usually over at that point).
Currently on one of the online go playing servers, GNU Go (among the top go playing programs -- though not the strongest) is roughly around 11 kyu in strength, A weak dan player can give gnugo a 9 stone handicap and the dan player will still win.
Several years ago, Janice Kim gave the top go playing program a 28 stone handicap and she still won the game (I believe it was a 28 stone game).
To get to a professional level player, it is best to start playing when you are very young. Expect to dedicate your life to the game. To get to a strong amateur dan level, also expect to dedicate a good chunk of your life to the game.
His name is Eric van der Werf.
a professor at the University of Maastricht
He is not a professor. He was a Ph.D. student. He received his Ph.D. title January 27 of this year.
in Holland.
That should be "The Netherlands". Holland is part of The Netherlands, but Maastricht is not located in Holland.
At about a quarter of the full-board version, 5x5 go
That's about 1/14th of a full board (25 points as opposed to 361 points).
is miniscule, similar in scale to "solving" 2X2 chess.
It is similar to solving 5x5 or 6x6 chess.
The fact that a programmer
Calling Van der Werf a "professor" is a bit too much, but calling him a "programmer" is not enough.
would even consider this a noteworthy challenge is itself a remarkable testament to the game's complexity.
Basically, it was not done before, and could be done with a couple of weeks computation time. That's not to belittle Eric's work; it is only a small part of his work. Read his thesis to see what he has done for the field of Go research.
Van Der Werk's
Again, it is "Van der Werf".
approach is described in detail in an article at the Netherlands Organization for Scientific Research (NOSR).
That should be NWO, not NOSR, and the approach is not described in detail in the article. For details, visit Eric's website.