It is currently Wed Oct 20, 2021 4:04 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 13 posts ] 
Author Message
Offline
 Post subject: Scoring and "dead" pieces
Post #1 Posted: Tue Aug 24, 2021 5:51 am 
Beginner

Posts: 4
Liked others: 0
Was liked: 1
I am relatively new ot Go, and have only played a couple of games. My biggest issue is with scoring (it's the same problem for all scoring systems I have come in contact with).
The problem I face is this:
How to evaluate a position in my head (scoring wise) if the game ends on "agreement"?
Or rather: What rule stops a player from placing pieces inside the opponents clearly controlled area like this:

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | . O . . . . X
$$ | . . . . O . X
$$ | . . O . . . X
$$ | O . . . . O X
$$ | . . . O . . X
$$ | . O . . . . X
$$ | . . . . O . X
$$ | X X X X X X X[/go]


Each piece requires 4 opponent's pieces to be taken. If I simply refuse to accept them as captured, what can the opponent do, but to capture, and lose 2 points per piece I play?
After all, a taken piece gives 1, and the spot it took gives 1, but since opponent needs to place 4 own pieces inside the own territory, it costs 2 pieces (by my count).

Where am I wrong in this?

It would help me a great deal to understand this issue, because it is a constant blocker in my head about how this game is correctly played.


Last edited by TreffnonX on Wed Aug 25, 2021 1:30 am, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #2 Posted: Tue Aug 24, 2021 6:42 am 
Honinbo

Posts: 9272
Liked others: 1558
Was liked: 1612
KGS: Kirby
Tygem: 커비라고해
There are different ways of addressing this. The AGA rules have the concept of a "pass stone". When you want to pass, you give an opponent one of your pass stones.

In a situation like you describe, where players disagree on the status of a single stone inside white territory, play can resume. White can play 4 stones to capture the stone, but black must play moves on his turn, too. If black has no place to play, black's move is a pass, which means that black would give white a pass stone for each turn. So yes, white "loses" 4 points by capturing the stone. But this is compensated by the pass stones received from black.

Some rules, IIRC, also have a "confirmation phase" or something where you can play out the theoretical moves without having the score impacted. But I like the pass stone method, as you can often just play the game out indefinitely without hurting the score balance.

_________________
be immersed

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #3 Posted: Tue Aug 24, 2021 7:10 am 
Beginner

Posts: 4
Liked others: 0
Was liked: 1
So if AGA rules specifically address this, can it be said, that certain (probably more classic) rules do not sufficiently address this (or not at all)?
To me, the AGA solution seems plausible, but I Do not understand the virtual play solution yet. When would that Beginn? The moment both players pass in sequence? That would make sense, to then end scoring, and just continue territoriale Resolution, without "filling" actual Space.

Overall my current takeaway is, that the turnout is heaviely dependent on the rules, and that what I describe is an actual problem with certain setups.

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #4 Posted: Tue Aug 24, 2021 7:35 am 
Lives in gote

Posts: 507
Liked others: 1
Was liked: 126
Rank: 13k
Knowing when a game is actually finished will only take a few dozen more games. Helps to play on the tiny 9x9 board with an experienced player, instead of a beginner at your same level who probably has the same misunderstandings (Beginner bots are almost useless for this kind of thing because they cannot explain it to you and will make stupid moves.)

Basically, you play it out till the status of groups becomes obvious. This learning technique is far easier to do using a real go set than online. Once you've thrashed out the status of a dozen or more unresolved groups, similar situations are more easily recognized and playing them out is no longer necessary. However, If you're focused on who wins rather than learning to understand this basic process, you may never get it.

I do not recommend using pass stones in your early learning phase. Just try to play for the fun of it and to practice working out the basic stuff.

_________________
David Bogie, Boise ID
I play go, I ride a recumbent, of course I use Macintosh.

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #5 Posted: Tue Aug 24, 2021 8:00 am 
Honinbo

Posts: 9272
Liked others: 1558
Was liked: 1612
KGS: Kirby
Tygem: 커비라고해
TreffnonX wrote:
Overall my current takeaway is, that the turnout is heaviely dependent on the rules, and that what I describe is an actual problem with certain setups.


Most of the time, the life/death status of a group is the same regardless of the ruleset. There are exceptions, but you can typically view a group as "dead" if the hypothetical alternate playout by both players results in the group being captured.

Some rulesets are more explicit about the resolution of dead groups, which is why I brought up the AGA rules. Some traditional rulesets seem to take a more intuitive approach to this, and are less precise (eg. there are some versions of Japanese rulesets, which are notoriously imprecise/bad).

As a newish player, I would play as if you were following the AGA rules for this situation, since resolution of dead groups is very clear. In situations where you are following a different ruleset, a tournament director or go server admin cam assist in resolving disputes.

But basically, you should consider things "alive" if the opponent cannot capture them, and "dead" if they can.

_________________
be immersed

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #6 Posted: Tue Aug 24, 2021 8:31 am 
Lives in gote

Posts: 380
Liked others: 0
Was liked: 32
TreffnonX wrote:
my current takeaway is, that the turnout is heaviely dependent on the rules, and that what I describe is an actual problem with certain setups.

Generally this is not a problem with any setup. Chinese-style (area) rules can play out cleanup moves without score change. Japanese-style (territory) can either play out with pass stones, or play out to see what happens then score the original stopped position accordingly. All three give identical results (normally within a point).

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #7 Posted: Tue Aug 24, 2021 1:56 pm 
Lives with ko

Posts: 199
Liked others: 17
Was liked: 20
Rank: panda 4 dan
IGS: kvasir
TreffnonX wrote:
I am relatively new ot Go, and have only played a couple of games. My biggest issue is with scoring [...]


If you post some game records we could help you with how to count the final position.

TreffnonX wrote:
To me, the AGA solution seems plausible, but I Do not understand the virtual play solution yet. [...]


Go is actually not a game of rules lawyering, "virtual play" or anything like that. At the end of the game the players will almost always just remove the dead stones of their own color and finish the game amicably.

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #8 Posted: Tue Aug 24, 2021 6:15 pm 
Lives in gote

Posts: 684
Liked others: 109
Was liked: 833
Rank: maybe 2d
TreffnonX wrote:
Overall my current takeaway is, that the turnout is heaviely dependent on the rules, and that what I describe is an actual problem with certain setups.


Your takeaway isn't correct. :) What you describe is a problem with none of the rules that people use. Every ruleset in wide use unanimously agrees that you cannot "gain" by playing a stone in the opponent's territory from the fact that they require 4 stones to capture it:

* Area scoring rules (Chinese, New Zealand, most computer-friendly rulesets) define your score to be the total spaces surrounded or occupied by your stones, and captures count for nothing. Placing a stone deep in the opponent's territory and having them play to kill it affects nothing, since the entire region will still end up surrounded or occupied by their stones and be scored all the same anyways.

* Many informal and casual Japanese/Korean rules (i.e. the way you'd actually play and resolve disputes in real life or in clubs with those rules), define your score to be the total spaces surrounded by your stones plus captures, and resolve disputes by *rewinding* back to the original position to score. If you play stones in the opponent's territory that cannot possibly live no matter what, the opponent just passes. Eventually you will run out of moves or have to pass yourself, so you pass too and the game ends. Then yes the opponent needs opponent to play 4 stones to capture your one stone, but once they play those stones and demonstrate that your one stone is dead, you always go back to the original position where the game first ended (the one after you both passed, but before they actually played those 4 extra stones) your one stone is declared dead as it stands, and you score from there.

* AGA rules achieve the same result as area scoring rules and allow you to physically play out disputes without having to rewind, while still allowing you to instead count stones plus captures, by through the previously described mechanism of pass stones. You can mathematically prove that the pass stones make the game equivalent to area scoring. So you can play the 4 stones to capture, and pass stones will make the result identical anyways.

* "Official" Japanese rules define things through an ambiguously-written and highly complicated system of hypothetical play which would be total waste of time for you to bother trying to understand, but also that when reasonably interpreted and fixed to best agree with the traditions and intentions of Japanese professionals, definitely do not have any such problem either.

---

The rules differences only have far more subtle consequences that do not matter if you are a beginner, and none of them have any problems of the sort that you're worried about, don't worry about them. Pick what makes sense to you, and dive in and play and have fun, and ask experienced players for help when you come across a specific position that you don't understand. :)


This post by lightvector was liked by: dfan
Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #9 Posted: Wed Aug 25, 2021 1:24 am 
Beginner

Posts: 4
Liked others: 0
Was liked: 1
Thank you all for your answers so far, they are indeed very helpful. I understand, that most players agree on the end of the game and captured groups, but for me it is important to understand when this is the case, based on the theoretical progression of the game, if it was played out. Otherwise, how could I evaluate whether I should keep playing or pass.

The last answer by lightvector is actually the most insightful, to me. However I am not entirely sure about the second explanation.
Quote:
* Many informal and casual Japanese/Korean rules (i.e. the way you'd actually play and resolve disputes in real life or in clubs with those rules), define your score to be the total spaces surrounded by your stones plus captures, and resolve disputes by *rewinding* back to the original position to score. If you play stones in the opponent's territory that cannot possibly live no matter what, the opponent just passes. Eventually you will run out of moves or have to pass yourself, so you pass too and the game ends. Then yes the opponent needs opponent to play 4 stones to capture your one stone, but once they play those stones and demonstrate that your one stone is dead, you always go back to the original position where the game first ended (the one after you both passed, but before they actually played those 4 extra stones) your one stone is declared dead as it stands, and you score from there.

This answer assumes, that there *was* consecutive passes by both players. If one player just keeps playing without passing, until an area is sufficiently degenerated, then it still seems abusable to me, because I could still attack the position and force my opponent to play 4 for 2. I will try to demonstrate (keep in mind that I am new, and this might not make any sense after all).

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | ? ? ? X ? X O
$$ | ? ? ? X X X O
$$ | ? ? ? X ? X O
$$ | ? ? ? X X O O
$$ | ? ? ? X O O
$$ | ? ? ? X O .
$$ | X X X X O .
$$ | O O O O O .[/go]


In this trivial example, this corner is black territory. If the game continues regularly, white would probably not be able to gain two eyes inside the highlighted zone. But if as you suggest, black just passed, then white is eventually able to form two eyes (there is surely enough space). So without intervention, white will be able to score zone here (not realistically though). So if white starts out spamming territory, and black does not intervene (remember, this all happens before white first passes) then white might actually convert this into an actual attack. So black has to interfere and lose score?
To understand my problem better, assume the above example happens in a game scored with 'casual Jap/Kor' rules. You are white, and your opponent is black. If you pass, you lose by 1 point overall. Do you pass and therefore forfeit? Otherwise, what is your objective within that limited area, assuming that all other territory is solid?

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #10 Posted: Wed Aug 25, 2021 1:31 am 
Lives in sente
User avatar

Posts: 1313
Liked others: 114
Was liked: 412
There is no point for White to invade that territory. If a sequence

:w1: :b2: :w3: :b4: :w5: :b6: follows and the three white stones are dead, then Black played 3 times inside his territory (-3 points) but gets 3 extra prisoners (+3 points) so Black still wins.

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #11 Posted: Wed Aug 25, 2021 1:37 am 
Beginner

Posts: 4
Liked others: 0
Was liked: 1
jlt wrote:
There is no point for White to invade that territory. If a sequence

:w1: :b2: :w3: :b4: :w5: :b6: follows and the three white stones are dead, then Black played 3 times inside his territory (-3 points) but gets 3 extra prisoners (+3 points) so Black still wins.


I understand. Black just continues playing as well, and when white starts passing, just passes as well. Since as many black stones were played as there were white stones played, those balance out. If white tried to attack, but fails (as expected) to secure two eyes, then black will eventually score the full area, scorewise, in sum of open territory and prisoners.


This post by TreffnonX was liked by: jlt
Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #12 Posted: Wed Aug 25, 2021 5:45 am 
Lives in gote

Posts: 684
Liked others: 109
Was liked: 833
Rank: maybe 2d
Right. For each move where black is absolutely *sure* that even if they pass they can still capture all the stones thereafter (white still has no way to make two eyes even if black ignores it), black passes and white loses a point because they have one more dead stone than before. For each move where black is not sure, then black responds, and the score is unchanged.

As long as black plays conservatively to keep white's stones dead, white can only break even or lose points, never gain points.

Black never plays more moves than white until white passes, in which case black is free to pass too. Then after the game, black demonstrates how they can capture all white's dead stones showing that they are indeed dead. This may require additional moves, but black does not get charged the cost of those additional moves since the scoring is based on the position after the first two passes.

Top
 Profile  
 
Offline
 Post subject: Re: Scoring and "dead" pieces
Post #13 Posted: Wed Aug 25, 2021 6:55 am 
Gosei

Posts: 1520
Liked others: 830
Was liked: 505
Rank: AGA 3k KGS 1k Fox 2d
GD Posts: 61
KGS: dfan
TreffnonX wrote:
Thank you all for your answers so far, they are indeed very helpful. I understand, that most players agree on the end of the game and captured groups, but for me it is important to understand when this is the case, based on the theoretical progression of the game, if it was played out. Otherwise, how could I evaluate whether I should keep playing or pass.

I strongly recommend that you play with Chinese or AGA rules for now (in fact, I recommend this to all beginners), in which there is no cost (except for opportunity cost) associated with continuing to play, and there are no agonizing "should I pass? but then is the game really over? are these stones really dead?" issues - just keep playing and take the stones off the board by capturing if you feel like it. When you are stronger it will be more obvious in more cases when you can stop earlier.

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group