Re: [computer-go] Human Learning against MoGo

2009-02-17 Thread Nick Wedd
In message <8b686dd80902161848q5fe39a83o56a934c089692...@mail.gmail.com>, Eric Boesch writes An amateur 5D also beat Mogo with 3 handicap. I would love to see more serious games between top programs and roughly evenly matched human opponents. Some are listed at http://www.computer-go.info/h-c

Re: [computer-go] Fuego performance

2009-02-17 Thread Markus Enzenberger
terry mcintyre wrote: Does Fuego make use of multiple cores? Does it require some switch setting to do so? The number of threads is controlled by the GTP command "uct_param_search number_threads". On Intel and AMD CPUs, you should also set ""uct_param_search lock_free 1", see http://www

Re: [computer-go] Congratulations to David Fotland and Many Faces

2009-02-17 Thread Bob Hearn
On Feb 16, 2009, at 5:45 PM, Andy wrote: See attached a copy of the .sgf. It was played private on KGS so you can't get it there directly. One of the admins cloned it and I saved it off locally. I changed the result to be B+4.5 instead of W+2.5. Here is another copy of the game record, wit

[computer-go] static evaluators for tree search

2009-02-17 Thread George Dahl
At the moment I (and another member of my group) are doing research on applying machine learning to constructing a static evaluator for Go positions (generally by predicting the final ownership of each point on the board and then using this to estimate a probability of winning). We are looking for

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread Jason House
I'd be more than happy to work with you and the other members of your group. I'm getting close to wrapping up a restructuring of my bot that allows easily swapping out evaluation methods and search techniques. As an example, here's the code that does a few basic MC searches: 11 static if (s

[computer-go] Re: static evaluators for tree search

2009-02-17 Thread Dave Dyer
While your goal is laudable, I'm afraid there is no such thing as a "simple" tree search with a plug-in evaluator for Go. The problem is that the move generator has to be very disciplined, and the evaluator typically requires elaborate and expensive to maintain data structures. It all tends to b

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread George Dahl
I am aware such a decoupled program might not exist, but I don't see why one can't be created. When you say the "move generator has to be very disciplined" what do you mean? Do you mean that the evaluator might be used during move ordering somehow and that generating the nodes to expand is tightl

[computer-go] Re: static evaluators for tree search

2009-02-17 Thread Dave Dyer
>Do you mean that the evaluator might be used during move ordering somehow >and that generating the nodes to expand is tightly coupled with the static >evaluator? That's the general idea. No search program can afford to use a fan-out factor of 361. The information about what to cut has to co

[computer-go] Re: static evaluators for tree search

2009-02-17 Thread Dave Dyer
>Do you mean that the evaluator might be used during move ordering somehow >and that generating the nodes to expand is tightly coupled with the static >evaluator? That's the general idea. No search program can afford to use a fan-out factor of 361. The information about what to cut has to co

RE: [computer-go] static evaluators for tree search

2009-02-17 Thread dave.devos
A simple alfabeta searcher will only get a few plies deep on 19x19, so it won't be very useful (unless your static evaluation function is so good that it doesn't really need an alfabeta searcher) Dave Van: computer-go-boun...@computer-go.org namens George Dahl

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread George Dahl
You're right of course. We have a (relatively fast) move pruning algorithm that can order moves such that about 95% of the time, when looking at pro games, the pro move will be in the first 50 in the ordering. About 70% of the time the expert move will be in the top 10. So a few simple tricks li

[computer-go] Re: static evaluators for tree search

2009-02-17 Thread Dave Dyer
This is old and incomplete, but still is a starting point you might find useful http://www.andromeda.com/people/ddyer/go/global-eval.html General observations (from a weak player's point of view): Go is played on a knife edge between life and death. The only evaluator that matters is "is thi

RE: [computer-go] static evaluators for tree search

2009-02-17 Thread Don Dailey
On Tue, 2009-02-17 at 20:04 +0100, dave.de...@planet.nl wrote: > A simple alfabeta searcher will only get a few plies deep on 19x19, so > it won't be very useful (unless your static evaluation function is so > good that it doesn't really need an alfabeta searcher) I have to say that I believe this

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread George Dahl
I really don't like the idea of ranking moves and scoring based on the distance to the top of a list for a pro move. This is worthless if we ever want to surpass humans (although this isn't a concern now, it is in principle) and we have no reason to believe a move isn't strong just because a pro d

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Michael Williams
George Dahl wrote: I guess the another question is, what would you need to see a static evaluator do to be so convinced it was useful that you then built a bot around it? Would it need to win games all by itself with one ply lookahead? Here is one way to look at it: Since a search tends to se

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread Erik van der Werf
On Tue, Feb 17, 2009 at 8:23 PM, George Dahl wrote: > It is very hard for me to figure out how good a given evaluator is (if > anyone has suggestions for this please let me know) without seeing it > incorporated into a bot and looking at the bot's performance. There > is a complicated trade off b

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Michael Williams
Michael Williams wrote: As for the source of applicable positions, that's a bit harder, IMO. My first thought was to use random positions since you don't want any bias, but that will probably result in the evaluation of the position being very near 0.5 much of the time. But I would still try

RE: [computer-go] static evaluators for tree search

2009-02-17 Thread dave.devos
I agree with you, but I wouldn't qualify MC evaluation with MCTS as a static evaluation function on top of a pure alfabeta search to a fixed depth (I have the impression that this is what George Dahl is talking about). Dave Van: computer-go-boun...@computer-go

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Gunnar Farnebäck
Dave Dyer wrote: > If you look at GnuGo or some other available program, I'm pretty sure > you'll find a line of code where "the evaluator" is called, and you could > replace it, but you'll find it's connected to a pile of spaghetti. That would have to be some other available program. GNU Go does

[computer-go] CGT approximating the sum of subgames

2009-02-17 Thread dave.devos
I've been looking into CGT lately and I stumbled on some articles about approximating strategies for determining the sum of subgames (Thermostrat, MixedStrat, HotStrat etc.) It is not clear to me why approximating strategies are needed. What is the problem? Is Ko the problem? Is an exact computa

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Jason House
On Feb 17, 2009, at 12:55 PM, Dave Dyer wrote: While your goal is laudable, I'm afraid there is no such thing as a "simple" tree search with a plug-in evaluator for Go. The problem is that the move generator has to be very disciplined, and the evaluator typically requires elaborate and expens

Re: [computer-go] CGT approximating the sum of subgames

2009-02-17 Thread Jason House
On Feb 17, 2009, at 4:39 PM, wrote: I've been looking into CGT lately and I stumbled on some articles about approximating strategies for determining the sum of subgames (Thermostrat, MixedStrat, HotStrat etc.) Link? It is not clear to me why approximating strategies are needed. What i

Re: [computer-go] CGT approximating the sum of subgames

2009-02-17 Thread terry mcintyre
From: Jason House On Feb 17, 2009, at 4:39 PM, wrote: I've been looking into CGT lately and I stumbled on some articles about approximating strategies for determining the sum of subgames (Thermostrat, MixedStrat, HotStrat etc.) Link? http://www.cs.rice.edu/

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Darren Cook
> I think it would be much more informative to compare evaluator A and > evaluator B in the following way. > Make a bot that searched to a fixed depth d before then calling a > static evaluator (maybe this depth is 1 or 2 or something small). Try > and determine the strength of a bot using A and a

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread George Dahl
Really? You think that doing 20-50 uniform random playouts and estimating the win probability, when used as a leaf node evaluator in tree search, will outperform anything else that uses same amount of time? I must not understand you. What do you mean by static evaluator? When I use the term, I

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread dhillismail
First, my code is in no shape for sharing. Some time back, I experimented with training a neural net to predict ownership maps from 9x9 board positions. I wasn't looking for a static evaluator; I wanted something to speed up my MCTS bot. I used my own engine to generate ownership maps for train

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Darren Cook
> Really? You think that doing 20-50 uniform random playouts and > estimating the win probability, when used as a leaf node evaluator in > tree search, will outperform anything else that uses same amount of > time? Same amount of clock time for the whole game. E.g. if playing 20 random playouts t

Re: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread Mark Boon
On Tue, Feb 17, 2009 at 8:35 PM, George Dahl wrote: > Really? You think that doing 20-50 uniform random playouts and > estimating the win probability, when used as a leaf node evaluator in > tree search, will outperform anything else that uses same amount of > time? You'll probably find a variet

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread terry mcintyre
From: "dhillism...@netscape.net" > Perhaps the biggest problem came from an unexpected quarter. MC playouts are > very fast and neural nets are a bit slow. (I am talking about the forward > pass, not the off-line training.) In the short time it took to feed a b

Re: [computer-go] static evaluators for tree search

2009-02-17 Thread George Dahl
GPUs can speed up many types of neural networks by over a factor of 30. - George On Tue, Feb 17, 2009 at 8:35 PM, terry mcintyre wrote: > > From: "dhillism...@netscape.net" > >> Perhaps the biggest problem came from an unexpected quarter. MC playouts >> are very

Re: [computer-go] Congratulations to David Fotland and Many Faces

2009-02-17 Thread Andy
On Mon, Feb 16, 2009 at 7:45 PM, Andy wrote: > See attached a copy of the .sgf. It was played private on KGS so you > can't get it there directly. One of the admins cloned it and I saved > it off locally. > > I changed the result to be B+4.5 instead of W+2.5. I forgot to make a disclaimer: I a

RE: [computer-go] Congratulations to David Fotland and Many Faces

2009-02-17 Thread David Fotland
I think you mean Many Faces of Go, not Crazystone. David > -Original Message- > From: computer-go-boun...@computer-go.org [mailto:computer-go- > boun...@computer-go.org] On Behalf Of Andy > Sent: Tuesday, February 17, 2009 10:08 PM > To: computer-go > Subject: Re: [computer-go] Congratula

RE: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread David Fotland
It is very clear that nonuniform random playouts is a far better evaluator than any reasonable static evaluation, given the same amount of time. Many people (including myself) spent decades creating static evaluations, using many techniques, and the best ones ended up with similar strength program

RE: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread David Fotland
Many Faces of Go has a static position evaluator, but it's not spaghetti :) It makes many passes over the board building up higher level features from lower level ones, and it does local lookahead as part of feature evaluation, so it has a lot of code, and is fairly slow. David > -Original Me

RE: [computer-go] static evaluators for tree search

2009-02-17 Thread David Fotland
It's not true that MCTS only goes a few ply. In 19x19 games on 32 CPU cores, searching about 3 million play outs per move, Many Faces of Go typically goes over 15 ply in the PV in the UCT tree. I agree that it is much easier to reliably prune bad moves in go than it is in chess. Many Faces (pre

RE: [computer-go] static evaluators for tree search

2009-02-17 Thread David Fotland
One way to figure out how good your static evaluator is, is to have it do a one ply search, evaluate, and display the top 20 or so evaluations on a go board. Ask a strong player to go through a pro game, showing your evaluations at each move. He can tell you pretty quickly how bad your evaluator

RE: [computer-go] Re: static evaluators for tree search

2009-02-17 Thread David Fotland
Many Faces uses information from the static evaluator to order and prune moves during move generation. For example if the evaluation finds a big unsettled group, the move generator will favor eye making or escaping moves for the big group. David > -Original Message- > From: computer-go-b