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Re: First Move Advantage in Pente
Posted:
Jul 3, 2011, 7:25 PM
I have to say about Gomoku solving because I take some part in this proces. We make software for Computer Olympiad in Maastricht 1990 which won the Olympiad in Gomoku. We use Japanese Joseki (Theory) as libroary of the program, and after the theory was ended the software was rather strong "Solver" DOS it can calculate win after the finishing the theory. That time the progremers try to write programs that was able to play without openning libroary. After that programers start to write programs with libroary and all solving Gomoku and other games just use Libroary. 10-15 years ago many Renju players try Pente , so D-Pente variant occur on influence Renju Rule of swap. Using swap rule in Renju make equal chences for P1 and P2, but many players say it is dull to play one or two opennings which give equal positions. So Renju starting investigations of openning rule again. In Pente I belive is easy to make libroary for computer program - use Top 3-4 players games as P1 and that will be tree of basic moves. that it will be rather easy to use software program to calculate the ends of the tree. All this moves you can write in libroary and may be prove of P1 advantage is ready.
Re: First Move Advantage in Pente
Posted:
Jul 4, 2011, 2:18 AM
I agree that Pente can be solved using computers, as I have previously written in another thread. But it is arguable that in practical terms an effectively balanced position could exist for human players.
Message was edited by: alisontate at Jul 6, 2011 10:18 AM
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Re: First Move Advantage in Pente
Posted:
Jul 7, 2011, 2:08 AM
Hey Alison! Great to hear from you -- hope all is going well.
I appreciate your description of the other side of the discussion, which you are calling "obscure". I usually speak of this concept as "complexity", although I admit that this word can have different meanings. In this context, we are speaking of an abstract idea of how "complicated" something is to a human mind, rather than something tangible and mathematical.
My response to the original question was focusing instead on the actual, inherant properties of the game with its given ruleset, which are rooted in math and logic. I touched on the fact that there is a perception of "more" or "less" advantage based on how complicated the position appears to humans, in general. However, even this can vary widely, and this is why the very best players, such as nosovs, often describe an important psychological component to the game. One aspect of this includes knowing and studying your opponent. The reason is that this opponent may have great familiarity with certain positions and is weak with some other positions. One position or line might be extremely complicated generally speaking, but if that player has studied this line in great detail and has played many successful games while using it, then the high complexity of the position is meaningless in this match since this player will perceive themselves to have great advantage due to their familiarity with the position.
I felt that the original question was about seeking a ruleset which would yield an actual equal position. My point is that there is no simple rule change to Pente which would make this happen.
I do like your description of no advantage consisting of a game which would go on forever. I agree with this. It is simple to dream up a ruleset which makes this happen. For example, try playing "50-in-a-row Gomoku" on an infinite-sized board. With perfect play, such a game would last forever, and therefore neither player has any built-in advantage. On a finite board, such a game would be expected to end in a Draw with perfect play, which again means that neither player had any built-in advantage.
A game of Pente with the Tournament Rule on a 19x19 board WILL end in victory for P1 with perfect play, NOT a Draw. Many experts agree that the number of moves required is likely less than 30. Therefore, P1 has an advantage under this ruleset. I was further pointing out that no simple rule change (including swap rules and so on) exists for Pente that changes this expectation from victory to Draw on a 19x19 board. In fact, with the current ruleset, there is no reasonable position that can be achieved through this ruleset that can be played out to a Draw with perfect play -- and therefore, one side or the other has the advantage in this position.
I don't know as much about Renju, but even with its complicated ruleset, I doubt that Renju mathematically provides "equal chances for both players" (with an infinite board size). However, with a finite board size, such as 19x19, there may be an expectation of a Draw with perfect play -- only because the combination of the restrictive rules and the small board do not allow for victory -- but not necessarily because the position is balanced.
Anyways, a lot of this has been discussed before and we are going down the rabbit hole again here. Hopefully this has been helpful to the player who posted the original question and he is getting a better grasp on these concepts after all of these responses!
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Re: First Move Advantage in Pente
Posted:
Jul 7, 2011, 2:18 AM
I realize that I am conflicting myself a bit here and in how I was describing these concepts in previous threads. It's possible that I'm changing my mind about certain points. For example, if a game has an expectation of ending in a Draw, or of going on forever, does either player have an advantage? Is such a position actually "balanced"? I think I may have been saying one thing before and another now regarding this. But, I think how these things are described is just academic, and the important points remain clear -- every reasonable position in Pente has an advantage for one side or the other and will end in victory. If we manufacture a position where all spaces on the board a filled except for one, which will end in a Draw when filled -- we might be tempted to claim that even with perfect play we have found a position with no advantage -- the response to this is that this is not a reasonable position that can be achieved with even reasonable play within the current ruleset.
Re: First Move Advantage in Pente
Posted:
Jul 9, 2011, 3:31 AM
Hey Dean, all is well thanks and I hope the same for you.
What I write here is more exposition than rebuttle..
It is acedemic if and only if there is no practical situation which exists as if there was no advantage even though mathematically there must be, such as in a pente game. Yes we can say with confidence that pente provides no escape for the inevitable loser with perfect play, but the reality is that people do not play perfectly.
My contention is that your argument is more acedemic than mine , since only in a parallel universe where everyone plays perfectly would all advantageous positions be converted to a win. In this universe this simply is not the case. A simple scan of the database proves this.
Complexity is similar but not the same thing as obscurity. Complexity does the obscuring. Things can be obscured by many things such as their inherent subtlety, or because detection of the nature of the advantage of a position requires visualisation of positions beyond a search horizon most humans can perform. Or it might be due to having two apparently equal choices and having unsufficient information to choose the right path (becuase you don't know your opponent's prepared plan), or any number of things really. Complexity is just one thing that can obscure the intrinsic advantage of a position, it is not the only thing.
The ability of a player to overcome the obscurity of a position is a key variable here. P2 will attempt to create obscurity for P1, and will succeed if P1's ability is insufficent to see through this and find the solution. As with all masters, the truth of this statement is bound up in the universal requirement to memorise openings and familiarise themselves with P2 responses in advance. This memorisation is a prophylactic against the only tool available to P2 - to obscure the first mover's advantage. P2 is forced to find a novel position so the obscurity of it has to be solved there and then in real time.
Effectively, the way that the masters play pente and approach the game entirely supports the position that it is appropriate to describe advantage in non-discrete terms for real play. There are two ingredients in all pente games these are the rules of pente and the human players. You cant do justice to the game by always describing it only in terms of perfect play. Yes, thats the ideal scenario, but for humans to understand the game they need to appreciate that advantage is a more sublte and multifaceted thing.
I could say for instance that even if the position is mathematically in your favour, that I have rendered the advantage so obscure that your prospects of finding the solution in real time are extremely low. Hense the advantage is really mine. This definition factors in real world situations.
As for the psychology, I think this more relates to how the player feels when confronted with uncertainty about what to do in a given situation. Different people respond differently to the same situation. For real people advantage is a matter of perception and can be a much more visceral thing than brute mathematics.
When masters prepare for a particular opponent, it is often not just for a position they may not have played before or played well, but for the tendancies of that player to respond certain ways to certain types of situations under pressure. In preparing in this way, you are acknowledging that the advantage you gain from this is not just a mathematical one.
As I said previously, if not for the entropic qualities of the pente rule set, a game (not pente) which had the capacity to be played forever could demonstrate the capacity for balanced positions, and would afford the opportunity to observe the limitations of the concept of discrete advantage.
Yes P1 with perfect play will win but in practice this is either rare or impossible in real time play. Therefore advantage is not simply a function of the mathematical properties of the game itself, but that of the combatants.
The Master's endless pursuit of P1 perfect openings is really an attempt to find certainty and avoid obscurity. To align their play as best they can with the intrinsic advantage provided mathematically by the rule-set. To come close to Plato's theoretical 'Form' for the game. This is the way Masters play the P1 V P2 arms race. The Masters do the opposite for P2 and search for a way to obsure the 'Form' for P1. Intrinsically we all know that advantage in practice is not black and white.
This war is a fascinating journey, and I have admiration for this who embark upon it with all their might.
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Re: First Move Advantage in Pente
Posted:
Jul 9, 2011, 8:32 AM
Great points Alison! You are a great writer and I tend to agree with your exposition here.
"There are two ingredients in all pente games these are the rules of pente and the human players."
I guess this was the same point that I was trying to make. Basically, there is the concept of advantage based on the intrinsic properties of the game and its rules. Then there is the perception of advantage and its gradient of strength by the players.
In my view, these are two seperate but related discussions. I believe that there are times when it's important to describe just the first concept, which is purely mathematical and based on perfect play, while making a conscious decision to disregard the second concept so that we don't confuse the issues. When a question arises about what the purpose of the Tournament Rule is and whether it can be changed in such a way as to create an equal position for both players, it's important to understand that technically this cannot exist for Pente, without introducing multiple, highly restrictive or arbitrary additional rules to the point that in my opinion the game ceases to be Pente and would have to be given a different name.
Once this is clear, then the question is, what happens if the rule is changed in some way, such as requiring the first move to be 4 spaces away instead of 3. Again, the most important point, IMO, is that such a change would not create an equal playing field. The result would be either a P1 advantage or a P2 advantage. This is based on the first of your two ingredients, the purely mathematical one.
Next, we can speak in terms of how strong the advantage is under each variation of the rule being considered -- ideally it would be best if players perceive that one rule variation causes the position to be "more equal" than the others. That's when we need your second ingredient in order to describe things accurately. For example, I believe that the swap rule provided by "D-Pente" yields a "more balanced" playing field than the standard Pro-Pente style of Pente using the Tournament Rule. There are a variety of reasons for this which become rather theoretical and subjective. Why? Because, in a purely mathematical sense, the advantage in D-Pente is the same as the one in Pro-Pente (except that D-Pente has a P2 advantage and Pro-Pente has a P1 advantage). The reason that the mathematical advantage is the same in both games is that once a position is established, the game is played out under the same set of rules.
I hope that I'm making some sense here -- I still sense that I am contradicting how I was thinking about and describing these concepts in earlier threads, but hopefully these can be reconciled by looking at the big picture.
Re: First Move Advantage in Pente
Posted:
Jul 10, 2011, 5:52 AM
Not to downplay the profundity of alison's statement, but I've had conversations with several top players (rich, zoey, up2ng, etc.) about the tradeoff between playing a strong, established P2 that your opponent knows how to handle versus playing a potentially weaker yet less familiar P2 in the hopes of catching your opponent off guard. I'm pretty sure this concept is universally known among high-level players since it basically defines P2's strategic options.
In my humble opinion, the most profound concept I've discovered on this site was up2ng exploring the dichotomy between beginner strategy, where you are advised to avoid making pairs as much as possible, and expert strategy, where I would say over half of strong P2 openings involve making a pair within the first four moves.
It's no use going back to yesterday, because I was a different person then.
Re: First Move Advantage in Pente
Posted:
Jul 11, 2011, 10:12 AM
Thanks HappyJ0!
Dean, in terms of the original question from theskald, some difficulties arise when we start to consider second move constraints for which we have no empirical data. We cannot say for certain the degree to which one version of the opening rule would affect the balance of power against another version without thousands of games being played and the same level of intense Master R&D developed over many tournements as the existing tournement rule. I think this point has been made in one way or another already.
This begs the question though: In regular Pente, can such changes to the opening ever be enough to address the P1 advantage to the degree that it becomes very close to zero? I mean, if it is desireable for that sort of balance to be achieved, then maybe it can't be achieved via only tweaking P1's 2nd move.
Perhaps the balance should be addressed another way, such as allowing P2 and only P2 to play boat pente rules. Or, P2 only needs 4 caps to win. I don't know if these sorts of things have been tried or considered.
Your comments on D-Pente are interesting, and I agree that once the swap occurs then mathematically the advantage, whether identifiable or not, exists with one or other player. However, what D-pente can do, is produce a much broader range or opening scenarios which are much more difficult to prepare for, and which can be far more obscure. The ideal scenario would be to have a mathematical advantage so small that it is beyond human ability to identify or at least at the limit of human ability. D-Pente has the potential to do this.
Having said that, I personally don't like the idea of D-Pente as it introduces an element of chance into the game.
Karl, your comments about the dichotomy of P2 strategems is interesting to me. Sorry if this has already been covered extensively elsewhere, but can you please elaborate on the value of playing a P2 line that is well known to your P1 opponent and that opponent knows how to handle?
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Re: First Move Advantage in Pente
Posted:
Jul 11, 2011, 1:09 PM
alison; >I personally don't like the idea of D-Pente as it introduces an element of chance into the game.
maybe im not understanding, but i'll say that in D-pente player 2 has sure win by default, for P2 gets to choose the winning side to play. P1 only decides if white or black has win, and is the under dog hoping to confuse the human P2 to choose the wrong side.
i have played a bit of D with arczi, and some of the most interesting opens of his yet have creatively involved designing it using "edge of the board" concepts. sadly many of these i think have been canceled games.
as for your idea of balancing using boat ideas and such, before u said this i had a thought involving viktor's wedge line where P2 wins in boat. and thought what if at that stage a new rule(s) kicked in to allow play to continue in a manner that fills the board with out the fear of captures sabotaging the draw.
and i still like my semi-untold idea of a variant involving dead stones on the grid. needing to work around them. and that these stones get introduced at certain moves like 3rd 7th 12th or what ever you like. and that both players get a chance to place these dead stones any where they like that is a open spot. and to take it further i had the idea to have stone bombs. yes both sides have exactly one bomb in their arsenal each. and at any point in time they can place the bomb in a open spot and obliterate all stones surrounding... meaning a maximum of 8 stones if you can visualize what im saying here. the bomb stone would then become a dead stone and the only stone remaining in the center of the after math of that 9 stone block explosion. and yes there should be a whistling sound before impact, then a bunch of fire, a loud roaring sound, and the table shakes back n forth for a moment when this occurs lol just imagine the psychological effects that could have. possibly named "atomic-pente" or "nuke-pente". err or some thing...
p.s., as to your question to karl, i think i can take a shot at answering it, but i'll wait to see if he replies first.
Scire hostis animum - Intelligere ludum - Nosce te ipsum - Prima moventur conciliat - Nolite errare
Re: First Move Advantage in Pente
Posted:
Jul 11, 2011, 3:56 PM
Thanks Zoey.
The element of chance in D-Pente is that no-one knows which set of stones, black or white, will be chosen by P2 until that choice is made. There is a 50:50 default chance of chosing black or white. This choice is informed by the position of the stones and determined by what the chosing player is able to make of the position. That judgement is imperfect, so in that sense there is no default win for P2. You could say that in a universe where only perfect pente moves are made, that D-Pente is a default win for P2, but in our universe there is a strong chance element involved IMO.
Your idea of exploding stones is interesting, reminds me of the game Minesweeper. In my physical board game of Pente there are these green stones which can be used by either player as part of their 5 in a row, or for performing a capture. I kinda like that idea.
Re: First Move Advantage in Pente
Posted:
Jul 12, 2011, 8:01 AM
To Allison:
Look at the history of the wedge opening. Of all the P2 lines in pente, it is unquestionably the most extensively studied. You would imagine that this familiarity would lead top-tier players to shy away from using it in tournament play because clearly P1 knows how to answer every conceivable attack. On the contrary, several players have used the wedge to great advantage in recent tournaments and continue to do so. It seems logical to presume that there is a strong correlation between the popularity of an opening among skilled P2s and its likelihood of its success against a skilled P1.
It's no use going back to yesterday, because I was a different person then.
Re: First Move Advantage in Pente
Posted:
Jul 13, 2011, 3:04 AM
To Karl
Since you have written your conclusion before your premise in your last post, I'll take your last sentence first.
"It seems logical to presume that there is a strong correlation between the popularity of an opening among skilled P2s and its likelihood of its success against a skilled P1. "
Clearly you would hope that P2s would not continue with lines that always led to a loss! This sentence is actually the premise of your argument. While obviously true in itself, its truth does not lead to your conclusion, which is that P2s play this even though "P1s know every conceivable attack".
Your conclusion (which I will paraphraze below) was: "..Look at the history of the wedge opening. Of all the P2 lines in pente, it is unquestionably the most extensively studied. You would imagine that this familiarity would lead top-tier players to shy away from using it in tournament play because clearly P1 knows how to answer every conceivable attack" Paraphrasing: "The popularity of the wedge opening is due to its success which appears to be being achieved even though P2s know that their P1 opponent will know how to handle whatever attack variant they come up with"
With respect, your conclusion seems contradictory to me. If skilled P2s routinely use the wedge opening with success in tournament play, then clearly their P1 opponents cannot answer every conceivable attack. And hence we should not be surprized at all with its continued use.
I think a better conclusion would be:
...that since the wedge opening is popular with P2s because of its success, and that success demonstrates that skilled P1s do not have the answer to every conceivable attack, then it must be that P2s continue to find novel positions (at least novel to their particular opponents) with the wedge opening that are sufficiently obscure that P1s cannot solve them in real-time.
It seems to me that what the P2s see in the wedge opening, is a strong base from which there are still myriad extensions into the unknown. A rich vein of positions for which the solution is highly obscure, such that P1s have a higher than normal failure rate in real time play. This is what keeps them using the opening and what leads to many P2 wins.
Re: First Move Advantage in Pente
Posted:
Jul 13, 2011, 8:27 AM
Alison said: and that success demonstrates that skilled P1s do not have the answer to every conceivable attack, then it must be that P2s continue to find novel positions (at least novel to their particular opponents) with the wedge opening that are sufficiently obscure that P1s cannot solve them in real-time.
I would posit that most of black's wedge wins are not novel positions, just positions where white's best response isn't absolutely clear, no matter how familiar he or she is with the line. With respect, I think you're misinterpreting the source of the strength of the wedge. Sure, every once in a while some one will beat an opponent with a novel variation, but most of P2's wins with the wedge in its 3,000-4000th iterations derived not from the element of surprise (contrary to other black wins with obscure openings), but instead from black's excellent position with regard to caps, making it exceedingly difficult for white to safely maneuver to a pente.
Also guys, 1,000 word essay responses make reading this thread kind of cumbersome. Practice concision.
It's no use going back to yesterday, because I was a different person then.
just imagine the psychological effects that could have.