Re: [computer-go] 3-4-5 rule
After 39 games it looks pretty close: Rank Name Elo+- games score oppo. draws 1 d3p 2009 55 5539 51% 20000% 2 base 2000 55 5539 49% 20090% confidence interval still too high to say for sure, but it is starting to appear that depth 2 works better. - Don On Tue, 2008-12-30 at 23:22 +0100, Heikki Levanto wrote: > On Tue, Dec 30, 2008 at 02:01:29PM -0500, Don Dailey wrote: > > It looks like 3 is no good: > > > > Rank Name Elo+- games score oppo. draws > >1 base 2000 296 199 3 67% 18880% > >2 d3p 1888 199 296 3 33% 20000% > > > > I think I have proven decisively that 3 doesn't work, it lost 2 out of > > the 3 games I played :-) > > So sorry, but as far as I can see, three games don't prove very much. Could > you please run at least 10 games more, before jumping into conclusions. > > -H > ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] 3-4-5 rule
On Wed, 2008-12-31 at 17:59 +0200, Berk Ozbozkurt wrote: > Heikki Levanto wrote: > > On Tue, Dec 30, 2008 at 08:01:27PM +0200, Berk Ozbozkurt wrote: > > > >> I think such a change may make engine objectively stronger while making > >> it more vulnerable against humans. Even if the human opponent isn't > >> aware of the move pruning logic initially, it wouldn't take a lot of > >> games to figure out that the computer never makes a move away from the > >> last move to the center or to the sides. > >> > > > > So sorry, but I think you have misunderstoodthe rule being tested here. It > > has nothing to do with the last move played, it is all about *not* playing > > to > > a point that is more than 3 (or 2) poitns away from any stone on the board, > > *or* that is on the 3th 4th, or the 5th row from the edge. > > > > This still leaves open a possibility of setting up two ladders, so that a > > ladder break somewhere in the center would be the right move. But even then, > > the random nature of the MC playouts would make such a position look pretty > > bad, and direct the program away from it - which would most often be good > > playing style anyway. > > > My real mistake was thinking this was a tree searching engine. My all > points are moot as this was only ref-bot doing AMAF. > > Assume, for argument's sake, the rule is implemented in a searching go > engine and moves not conforming to the rule are hard pruned during > search. It doesn't matter whether 2 points from any stone or just last > move is considered. In many openings neither side would have any stones > near the center, so no moves to the center would be considered by the > engine, for at least a few more branches down the tree. Note that, it is > the human opponent, who makes losing ladders with the intention of > putting a ladder breaker in the center. As the program is oblivious to > the fact that only one ladder may be won by it, the program will > evaluate its position *highly* and tend to continue ladders as long as > human continues playing them. It is not necessary to construct an example - it's just understood that any imperfect rule can be taken advantage of. I think most game tree search expert understand that "hard pruning" is wrong in the sense that it produce non-scalable programs. It might make your program stronger in the short term as someone said, but you would now have some rule that a clever opponent can take advantage of such as the case you just constructed. No matter what hard pruning rule you come up with, someone can construct an example where it's wrong, unless of course the rule is 100 percent correct and fool-proof. You basically just set up a position where the opponent really must play the forbidden move knowing that he cannot see it. But that doesn't mean you should not use SOFT pruning or bias - even in the tree.In fact most progress in computer go and computer chess has been in shaping the tree using imperfect heuristics, sometimes domain specific.There is no convincing logic that I know of that says it's better NOT to do that. You can always construct an example of some position where it goes wrong, but go ahead and build a program with the principal of not using knowledge and I will show you an extremely weak program. The perfect example is humans. Full of contradiction, bias and imperfect knowledge. A clever enough player can take advantage of even the strongest human players with methods like you suggest. I think the key is that knowledge you add must be reasonable and practical. Generally, beginners are given good practical rules of thumb, that serve him well. But a good strong player following such rules religiously would be compromised. You see, the same rule can make one play much better, another much worse.The rule must be compatible with your competence. Image being able to construct hundreds of rules like the 3-4-5 rule that are applied in decision tree fashion. One can imagine the program playing better and better as you add more rules. At some point the program would reach a level of competence where you would have to reconsider some of the rules, because they are now hurting the program. The 3-4-5 rule might be good at first, but imagine (I know this is silly) that such a program reached several dan level. The 3-4-5 rule would have to be replaced, or refined with exceptions otherwise further progress is hindered. As a kid I did a paper program for chess that worked like this. You just followed the instructions and eventually a move was produced. The program was designed to delay development of the queen - because every beginner knows not to move your queen out early. So you could threaten the opponent in such a way that a queen move was required, and the "program" could not defend. But the program was so weak and primitive that it was still a good rule - i.e. better than no rule at all. - Don - Don >
[computer-go] wine and contact fights dojo
I recently bought Bruce Wilcox's Contact Fights Dojo, and had a bit of trouble getting it to work under WINE. Tried googling it, couldn't find any tips, eventually stumbled on a solution. This is probably second nature to people with more WINE experience, but I figure somebody else may google for the same problem, so here's my fix: WINE creates a ~/.wine/drive_c directory; under this is a Program Files directory. Move the Dojo directory under there, and invoke the program so: wine c:/Program\ Files/Dojo/dojo.exe WINE maps "C:" to ~wine/drive_c, and the dojo program then knows where the current working directory is located. HTH Terry McIntyre -- Libertarians Do It With Consent! ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Re: 3-4-5 rule
A two-space horizontal play is often the normal extension. ( but they tend to be from 3rd-line points, therefore already playable under the proposed rule ) Two-space vertical jumps are less common, but they are playable in some situations. I'm just a mid-kyu player, but I've seen much stronger players using two-space vertical jumps in certain cases. Terry McIntyre -- Libertarians Do It With Consent! - Original Message > From: Ingo Althöfer <3-hirn-ver...@gmx.de> > To: computer-go@computer-go.org > Sent: Wednesday, December 31, 2008 12:50:48 AM > Subject: [computer-go] Re: 3-4-5 rule > > Hello Don, > > > The reference bot of course does not build a tree, what I'm actually > > looking for is a way to produce a medium strength but really simple bot > > that does not build a tree and just has a lot of playout magic. > > You should have stressed very clearly much earlier > in the thread that no tree is built. > > By the way, there is some in-between parameter between distance 2 > and distance 3: > * all distance 2-(Manhattan)-paths are allowed: nn, ee, ss, ww, ne, en, es, > se, > ... > * among the distance 3-paths only those are allowed which do not have all > three steps in the same direction: this rule would forbid only the four paths > , , sss, www would be forbidden. > > (Here n, e, s, w indicate the four basic directions "north", ..., "west".) > > Ingo. > > > -- > Pt! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: > http://www.gmx.net/de/go/multimessenger > ___ > computer-go mailing list > computer-go@computer-go.org > http://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] 3-4-5 rule
Heikki Levanto wrote: On Tue, Dec 30, 2008 at 08:01:27PM +0200, Berk Ozbozkurt wrote: I think such a change may make engine objectively stronger while making it more vulnerable against humans. Even if the human opponent isn't aware of the move pruning logic initially, it wouldn't take a lot of games to figure out that the computer never makes a move away from the last move to the center or to the sides. So sorry, but I think you have misunderstoodthe rule being tested here. It has nothing to do with the last move played, it is all about *not* playing to a point that is more than 3 (or 2) poitns away from any stone on the board, *or* that is on the 3th 4th, or the 5th row from the edge. This still leaves open a possibility of setting up two ladders, so that a ladder break somewhere in the center would be the right move. But even then, the random nature of the MC playouts would make such a position look pretty bad, and direct the program away from it - which would most often be good playing style anyway. My real mistake was thinking this was a tree searching engine. My all points are moot as this was only ref-bot doing AMAF. Assume, for argument's sake, the rule is implemented in a searching go engine and moves not conforming to the rule are hard pruned during search. It doesn't matter whether 2 points from any stone or just last move is considered. In many openings neither side would have any stones near the center, so no moves to the center would be considered by the engine, for at least a few more branches down the tree. Note that, it is the human opponent, who makes losing ladders with the intention of putting a ladder breaker in the center. As the program is oblivious to the fact that only one ladder may be won by it, the program will evaluate its position *highly* and tend to continue ladders as long as human continues playing them. ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re: [computer-go] 3-4-5 rule
On Wed, 2008-12-31 at 14:45 +0100, Heikki Levanto wrote: > Of course a clever player who > knows about this can direct the game so that he ends with a moyo, > where the > optimal reduction move does not get considered. That sounds tricky, > and the > advantage from such is slight, he can be a tiny bit more confident of > keeping > his moyo... A player sophisticated enough to even think about doing this is way beyond the level of a simple reference bot using this strategy in the playouts.In fact, even trying to win like this would probably weaken him a little. Why go to the trouble when it's so easy to win other ways? I would love it if my much stronger opponents were to try to get clever on me when they didn't have to. Like this same chess master told me, keep it simple, don't get too clever when you don't have to. - Don ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re: [computer-go] 3-4-5 rule
On Wed, Dec 31, 2008 at 12:25:01PM +, p...@tabor.com wrote: > I think Heikki makes a valid point here. I am not a particularly strong > player (about 1-2 dan european), but I have learned that playing > defensively is generally detrimental to the final result, whereas taking > the initiative is more likely to lead to a win. If moves close to the > existing position are given much greater weight than those further away, > this may result in more defensive play than otherwise. Actually, as I undersand it, the rule was not to play close to the opponent's last move, but to limit play to either - 3rd, 4th, or 5th row - near any stone already played. This makes much more go-sense to me, even though I am a weak player (something like 5 kyu in Denmark). This rule will allow most of the common side extensions, invasions, etc, as well as answering any move locally or not. It will disallow some few moyo-reducing moves, but not too many. I guess in most cases those moyos can also be reduced by playing close enough to other stones, and/or on the 4th or 5th line. Of course a clever player who knows about this can direct the game so that he ends with a moyo, where the optimal reduction move does not get considered. That sounds tricky, and the advantage from such is slight, he can be a tiny bit more confident of keeping his moyo... - Heikki -- Heikki Levanto "In Murphy We Turst" heikki (at) lsd (dot) dk ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re: [computer-go] 3-4-5 rule
On Wed, 2008-12-31 at 12:25 +, p...@tabor.com wrote: > I think Heikki makes a valid point here. I am not a particularly > strong player (about 1-2 dan european), but I have learned that > playing defensively is generally detrimental to the final result, > whereas taking the initiative is more likely to lead to a win. This is how I feel about playing in general, but it's better stated by what a chess master once told me: "Play your own game." From his own experience he told me that weaker players often get intimidated when they play a master and play worse than they normally would. Also they avoid tactics even when that is the strongest part of their game feeling that they will surely get crushed. So the advice is to just do what you do best, play your strengths. > If moves close to the existing position are given much greater weight > than those further away, this may result in more defensive play than > otherwise. As I said before, for a weak bot this is not really a matter of playing inferior to what it is capable of. We are talking about a random strategy and playing moves that are much more likely to be good than random moves is probably not a defensive losing strategy in my opinion. I don't have a strong opinion on how good the actual strategy 3-4-5 strategy is however, I'm not much of a go player.How often is this rule violated in top level games?And when it is, can it be shown that no reasonable conforming rule exists? I don't know the answer to that. > > During much of the game, most moves between human players, even at > professional level, are played near to the previous move. So > considering all moves near to the last played move is likely to > increase the probablility of selecting the best move. This could be > the factor that is currently resulting in more wins where the 3-4-5 > rule is applied. The issue is whether resulting in more wins is correlated to playing stronger in the general case against a variety of opponents.So if one bot is NOT using this strategy and the other IS using this strategy, then one of them is not biased in this regard, yet it is losing. The conclusion I would draw here is that with high probability the one using the strategy is actually playing a better overall game. This is the simplest and most "Occam's razor" conclusion. If the bot was far stronger and much more sophisticated, then this is a rule which might very well hold it back. > > However, there are times when the best move is most definitely not in > the vicinity of the previous one, and a strong player will 'tenuki' - > i.e. leave that part of the position to play something more important > elsewhere - an urgent invasion on the other side of the board for > example. If computer go programmes are to become truly strong they > will need to have a way to emulate this kind of approach. I don't think that is in question. What is being called into question is whether there should be any kind of rules or evaluation that might occasionally be in error. The answer is crystal clear, all strong go programs have biased playouts and it works. > > In my (limited) opinion, the 3-4-5 rule may result in a short-term > gain, but will require refinement in due course to allow for what > human players might call creativity. I agree. To me this is like a chess evaluation function, nobody has every written a good one but they work really well anyway. You could do without one and watch your program get really weak. Random playouts by themselves probably never will advance beyond horrible play and thus approximate rules can be a big win. - Don > > Paul > > > > Dec 30, 2008 11:56:58 PM, computer-go@computer-go.org wrote: > > > On Wed, Dec 31, 2008 at 12:25:10AM +0100, Rémi Coulom wrote: > > > > If you'd like to try a simple pruning scheme that improves > playing > > strength on 19x19, then I'd suggest progressive widening. It > only works > > in the tree, not in the playouts. You don't need complex > patterns for > > progressive widening to work. You can simply use distance to > the > > previous move. Search moves at distance 1 from the previous > move for N > > playouts. Then add moves at distance 2 for N*x playouts. > Moves at > > distance 3 for N*x*x. > > > So, you'd be playing like a beginner, with a local answer to > every move the > opponent makes. Never taking sente to play elsewhere. Sounds > like a receipe > for a disaster to me. But then again, I am only a kyu-level > player, so I may > be wrong... > > -H > > -- > Heikki Levanto "In Murphy We Turst" heikki (at) lsd > (dot) dk > > ___ > computer-go mailing list >
Re: Re: [computer-go] 3-4-5 rule
I think Heikki makes a valid point here. I am not a particularly strong player (about 1-2 dan european), but I have learned that playing defensively is generally detrimental to the final result, whereas taking the initiative is more likely to lead to a win. If moves close to the existing position are given much greater weight than those further away, this may result in more defensive play than otherwise. During much of the game, most moves between human players, even at professional level, are played near to the previous move. So considering all moves near to the last played move is likely to increase the probablility of selecting the best move. This could be the factor that is currently resulting in more wins where the 3-4-5 rule is applied. However, there are times when the best move is most definitely not in the vicinity of the previous one, and a strong player will 'tenuki' - i.e. leave that part of the position to play something more important elsewhere - an urgent invasion on the other side of the board for example. If computer go programmes are to become truly strong they will need to have a way to emulate this kind of approach. In my (limited) opinion, the 3-4-5 rule may result in a short-term gain, but will require refinement in due course to allow for what human players might call creativity. Paul Dec 30, 2008 11:56:58 PM, computer-go@computer-go.org wrote: On Wed, Dec 31, 2008 at 12:25:10AM +0100, Rémi Coulom wrote:> > If you'd like to try a simple pruning scheme that improves playing > strength on 19x19, then I'd suggest progressive widening. It only works > in the tree, not in the playouts. You don't need complex patterns for > progressive widening to work. You can simply use distance to the > previous move. Search moves at distance 1 from the previous move for N > playouts. Then add moves at distance 2 for N*x playouts. Moves at > distance 3 for N*x*x. So, you'd be playing like a beginner, with a local answer to every move theopponent makes. Never taking sente to play elsewhere. Sounds like a receipefor a disaster to me. But then again, I am only a kyu-level player, so I maybe wrong... -H-- Heikki Levanto "In Murphy We Turst" heikki (at) lsd (dot) dk___computer-go mailing listcomputer-go@computer-go.orghttp://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] Re: 3-4-5 rule
I am sorry for my typos (with and ). Of course I meant: * among the distance 3-paths only those are allowed which do not have all three steps in the same direction: this rule would forbid only the four paths nnn, eee, sss, www. Ingo -- Sensationsangebot verlängert: GMX FreeDSL - Telefonanschluss + DSL für nur 16,37 Euro/mtl.!* http://dsl.gmx.de/?ac=OM.AD.PD003K1308T4569a ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] Re: 3-4-5 rule
Hello Don, > The reference bot of course does not build a tree, what I'm actually > looking for is a way to produce a medium strength but really simple bot > that does not build a tree and just has a lot of playout magic. You should have stressed very clearly much earlier in the thread that no tree is built. By the way, there is some in-between parameter between distance 2 and distance 3: * all distance 2-(Manhattan)-paths are allowed: nn, ee, ss, ww, ne, en, es, se, ... * among the distance 3-paths only those are allowed which do not have all three steps in the same direction: this rule would forbid only the four paths , , sss, www would be forbidden. (Here n, e, s, w indicate the four basic directions "north", ..., "west".) Ingo. -- Pt! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
