Re: [computer-go] new kid on the block

2009-08-12 Thread Isaac Deutsch
Congrats for breaking the 1000 elo mark on cgos. ;) Some things I noticed when watching 2 games: -stop plays on the first line/corner in the beginning. maybe this helps: http://computer-go.org/pipermail/computer-go/2008-December/017340.html or this:

Re: [computer-go] new kid on the block

2009-08-12 Thread Folkert van Heusden
Congrats for breaking the 1000 elo mark on cgos. ;) Thanks! Version 0.5 made quiet a difference compared to version 0.4. I'm graphing the elo ratings of the versions running at cgos here: http://keetweej.vanheusden.com/stats/stop-all-elo-cgos.png Some things I noticed when watching 2 games:

Re: [computer-go] new kid on the block

2009-08-12 Thread Don Dailey
Yes, known problem :-( I'm still trying to find a method to see if a point is in an eye. Should not be too difficult in theory but in practice i have not found a method yet. Are you talking about 1 point eyes? For this I think most programs use the same definition, which is quite good

[computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Ingo Althöfer
In the last few weeks I have experimented a lot with dynamic komi in games with high handicap. Especially, I used the really nice commercial program Many Faces of Go (version 12.013) with its Monte Carlo level (about 2 kyu on 19x19 board) and its traditional 18-kyu level as the opponent. At

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
2009/8/12 Ingo Althöfer 3-hirn-ver...@gmx.de In the last few weeks I have experimented a lot with dynamic komi in games with high handicap. Especially, I used the really nice commercial program Many Faces of Go (version 12.013) with its Monte Carlo level (about 2 kyu on 19x19 board) and its

[computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Brian Sheppard
The small samples is probably the least of the problems with this. Do you actually believe that you can play games against it and not be subjective in your observations or how you play against it? These are computer-vs-computer games. Ingo is manually transferring moves between two computer

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
Ingo suggested something interesting - instead of changing the komi according to the move number, or some other fixed schedule, it varies according to the estimated winrate. It also, implicitly, depends on one's guess of the ability of the opponent. An interesting test would be to take an

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
Ok, I misunderstood his testing procedure. What he is doing is far more scientific than what I thought he was doing. There has got to be something better than this. What we need is a way to make the playouts more meaningful but not by artificially reducing our actual objective which is to

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
Consider this thought experiment. You sit down at a board and your opponent has a 9-stone handicap. By any objective measure of the game, you should resign immediately. All your win-rate calculations report this hopeless state of affairs. Winrate gives you no objective basis to prefer one

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread dhillismail
I think Terry's suggestion is the best way to test these ideas: 1) Take 2 severely mismatched engines (perhaps 2 versions of the same engine but with different numbers of playouts.) 2) Find the fair handicap by playing a sequence of games and adjusting the number of handicap stones whenever

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
The problem with MCTS programs is that they like to consolidate. You set the komi and thereby give them a goal and they very quickly make moves which commit to that specific goal. Commiting to less than you need to actually win will often involve sacrificing chances to win.Sometime it

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
Terry, I understand the reasoning behind this, your thought experiment did not add anything to my understanding. And I agree that if the program is strong enough and the handicap is high enough this is probably better than doing nothing at all. However, I think there must be something that

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Ivan Dubois
I 100% agree with Don, dynamic komi just cant be the right approach in my opinion. One idea I just have is this : In the tree search part, instead of using a rule wich converges to MAX, use a rule wich converges to alpha*MAX + beta*AVERAGE. Do this only for plies where it is the weaker player

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
Some algorithms are special-purpose by nature. What I sketched is an approximation of my understanding of how strong players defeat weaker players with large handicaps. When Myungwan Kim faced off against MFG a few days ago, with a 7 stone handicap, he had to come up with a strategy which would

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Mark Boon
I started to write something on this subject a while ago but it got caught up in other things I had to do. When humans play a (high) handicap game, they don't estimate a high winning percentage for the weaker player. They'll consider it to be more or less 50-50. So to adjust the komi at the

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
Most experiments are done on even games; this dynamic algorithm applies particularly to handicap games.In that context, it is not an ungainly kludge, but actually reflects the assessment of evenly matched pro players - they look at the board, and see a victory of n times 10 handicap stones ( or

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
On Wed, Aug 12, 2009 at 5:36 PM, Mark Boon tesujisoftw...@gmail.com wrote: I started to write something on this subject a while ago but it got caught up in other things I had to do. When humans play a (high) handicap game, they don't estimate a high winning percentage for the weaker player.

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
2009/8/12 terry mcintyre terrymcint...@yahoo.com Most experiments are done on even games; this dynamic algorithm applies particularly to handicap games.In that context, it is not an ungainly kludge, but actually reflects the assessment of evenly matched pro players - they look at the board,

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Mark Boon
2009/8/12 Don Dailey dailey@gmail.com: I disagree about this being what humans do.   They do not set a fake komi and then try to win only by that much. I didn't say that humans do that. I said they consider their chance 50-50. For an MC program to consider its chances to be 50-50 you'd

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
In practical terms, the problem to solve is the reverse: how do we encourage weak programs to hang on to as much of their advantage as possible, against stronger players? In 2020, we can worry about how to beat pro players who take large handicaps against computer programs. Terry McIntyre

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Matthew Woodcraft
Don Dailey wrote: The problem with MCTS programs is that they like to consolidate. You set the komi and thereby give them a goal and they very quickly make moves which commit to that specific goal. How did you form this opinion? Can you show an example game record (on 19x19) showing this

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
On Wed, Aug 12, 2009 at 5:58 PM, Mark Boon tesujisoftw...@gmail.com wrote: 2009/8/12 Don Dailey dailey@gmail.com: I disagree about this being what humans do. They do not set a fake komi and then try to win only by that much. I didn't say that humans do that. I said they consider

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Stefan Kaitschick
What a bot does with its playouts in a handicap situation is to essentially try to beat itself, despite the handicap. And in this situation the bot reacts in a very human way, it becomes despondend. Adjusting the komi dynamically shifts the goal from winning to catching up quickly enough. I

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
On Wed, Aug 12, 2009 at 6:03 PM, Matthew Woodcraft matt...@woodcraft.me.ukwrote: Don Dailey wrote: The problem with MCTS programs is that they like to consolidate. You set the komi and thereby give them a goal and they very quickly make moves which commit to that specific goal. How did

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Don Dailey
2009/8/12 Stefan Kaitschick stefan.kaitsch...@hamburg.de What a bot does with its playouts in a handicap situation is to essentially try to beat itself, despite the handicap. And in this situation the bot reacts in a very human way, it becomes despondend. Adjusting the komi dynamically

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Stefan Kaitschick
What seems difficult to me however is to devise a reasonable way to decrease this komi as the game progresses Certainly that is the main problem. But the main considerations are not so hard to find 1. Win rate of the best move. 2. How far has the game progressed 3. deviation between the win

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread terry mcintyre
As for how to beat weaker players ... the strong players whom I have observed make strong, stable positions; they wait for the weaker player to make mistakes. The stronger player will leave things unresolved for longer, knowing that there will be time to extend in one direction or another later

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Stefan Kaitschick
For instance I am sure he will not sit merrily by and watch his opponent consolidate a won game just so that he can have a respectable but losing score.Dynamic komi of course does not address that at all. This seems self evident, but it may actually be a treacherous conclusion. Dynamic

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Matthew Woodcraft
Don Dailey wrote: Matthew Woodcraft wrote: Don Dailey wrote: The problem with MCTS programs is that they like to consolidate. You set the komi and thereby give them a goal and they very quickly make moves which commit to that specific goal. How did you form this opinion? Can you

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Mark Boon
2009/8/12 Don Dailey dailey@gmail.com: If the program makes decisions about the best way to win N points,   there is no guarantee that this is ALSO the best way to win N+1 points. Although this is obviously true, that doesn't automatically mean it's not the best approach. Because there's a

[computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Brian Sheppard
No thought experiments are going to convince me on this subject. Someone will have to do an actual test. Ingo's work is the best to date on the subject. Anyone who is overly committed to thought experiments should consider that we are talking about applying MCTS to Go, that most deterministic of

Re: [computer-go] Monte-Carlo Simulation Balancing

2009-08-12 Thread Michael Williams
After about the 5th reading, I'm concluding that this is an excellent paper. Is anyone (besides the authors) doing research based on this? There is a lot to do. David Silver wrote: Hi everyone, Please find attached my ICML paper with Gerry Tesauro on automatically learning a simulation

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Christoph Birk
On Aug 12, 2009, at 2:51 PM, Don Dailey wrote: I disagree. I think strong players have a sense of what kind of mistakes to expect, and try to provoke those mistakes. Dynamic komi does not model that. It also does the opposite of making the program play provocatively, which I believe

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Christoph Birk
On Aug 12, 2009, at 3:10 PM, Don Dailey wrote: If the handicap is fair, their chance is about 50/50. However, rigging komi to give the same chance is NOT what humans do. The only thing you said that I consider correct is that humans estimate their chances to be about 50/50. One thing

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Petri Pitkanen
Maybe they are long way from giving handicaps to you. But best of bots in KGS are around 2k and there are hundreds of 9k and weaker players present there at all times. So being able to play white is worthy thing at least for commercial bot. Petri 2009/8/13 Christoph Birk b...@ociw.edu: On Aug

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Christoph Birk
On Aug 12, 2009, at 3:43 PM, Don Dailey wrote: I believe the only thing wrong with the current MCTS strategy is that you cannot get a statistical meaningful number of samples when almost all games are won or lost.You can get more meanful NUMBER of samples by adjusting komi, but

Re: [computer-go] Dynamic komi at high handicaps

2009-08-12 Thread Christoph Birk
On Aug 12, 2009, at 10:31 PM, Petri Pitkanen wrote: Maybe they are long way from giving handicaps to you. But best of bots in KGS are around 2k and there are hundreds of 9k and weaker players present there at all times. So being able to play white is worthy thing at least for commercial bot.