Re: [computer-go] Really basic question

2009-07-07 Thread terry mcintyre
megasnippage of Don's post: > Adding an additional order of magnitude more time to the search [ in Rybka] > is not going to change the basic misconception if the evaluation just doesn't understand the position. [ Don suggests that this applies even more so to Go ] Amen! We've covered variants o

Re: [computer-go] Really basic question

2009-07-07 Thread Don Dailey
On Tue, Jul 7, 2009 at 3:49 AM, Magnus Persson wrote: > Quoting Oliver Lewis : > > Others on this list have reported in the past that the randomness is >> actually very important. Playouts that are very heavy, no matter how >> "clever" they are, actually reduce the performance because they narro

Re: [computer-go] Really basic question

2009-07-07 Thread Christian Nentwich
Fred, others have already indicated that you are missing the "tree" part of Monte Carlo Tree Search, but there is something else to add. If you run uniform random playouts on an empty 9x9 board, let's say a million of them for each point, you will see a probability distribution emerging that

Re: [computer-go] Really basic question

2009-07-07 Thread Heikki Levanto
On Tue, Jul 07, 2009 at 09:16:25AM +0200, Oliver Lewis wrote: > > You should also read up on the "all moves as first" (AMAF) technique. This > is even more surprising because it attributes the outcome of a random game > to every move of that colour during the random game, as if that was the move

Re: [computer-go] Really basic question

2009-07-07 Thread Magnus Persson
Quoting Oliver Lewis : Others on this list have reported in the past that the randomness is actually very important. Playouts that are very heavy, no matter how "clever" they are, actually reduce the performance because they narrow the number of games too much. I would like to disagree with t

Re: [computer-go] Really basic question

2009-07-07 Thread Oliver Lewis
Although the number of games explored is very limited relative to the total number of possible games, those games are in some sense representative of what happens if you start with a particular move. That's why they can help to create a ranking that tells you something about which moves are better

Re: [computer-go] Really basic question

2009-07-06 Thread Raymond Wold
George Dahl wrote: I think he is missing the tree search part. Just doing a one-ply lookahead and then doing playouts will not make a strong bot. I would like to defer an explanation of UCT (or something else) to someone who is more of an expert. UTC would add little if MC itself were not a l

Re: [computer-go] Really basic question

2009-07-06 Thread Michael Williams
That's the beauty of MC! It really is a beautiful system. Initially, they were totally random playouts. But the more powerful MC Go engines do not do completely random playouts; they do "heavy" playouts. But if you were to look at a heavy playout, it would still look like a very weak Go player

Re: [computer-go] Really basic question

2009-07-06 Thread George Dahl
I think he is missing the tree search part. Just doing a one-ply lookahead and then doing playouts will not make a strong bot. I would like to defer an explanation of UCT (or something else) to someone who is more of an expert. - George On Mon, Jul 6, 2009 at 8:25 PM, Raymond Wold wrote: > Fred

Re: [computer-go] Really basic question

2009-07-06 Thread Raymond Wold
Fred Hapgood wrote: I have a really basic question about how MC works in the context of Go. Suppose the problem is to make the first move in a game, and suppose we have accepted as a constraint that we will abstain from just copying some joseki out of a book -- we are going to use MC to figure o

[computer-go] Really basic question

2009-07-06 Thread Fred Hapgood
I have a really basic question about how MC works in the context of Go. Suppose the problem is to make the first move in a game, and suppose we have accepted as a constraint that we will abstain from just copying some joseki out of a book -- we are going to use MC to figure out the first move de n