Yes, this is a general issue. With no komi, black has one more point than white in 1/2 of games (dame polarity). And whenever white has a fixed komi, black will still have one more point under area scoring than under territory scoring in 1/2 of games. But in fact, China has historically tended to offer one more point of komi (well, an extra 0.5 zi) in komi than the Japanese and Koreans do, so in practice it is white who has an extra point in 1/2 of games when people use area rules.

In effect, white's extra pass under AGA rules is a way to give back one point of the Chinese-style 7.5 komi (if I understand correctly). I'm sure I will swiftly corrected by someone who is better at arithmetic...

The Japanese dame makes jigo possible for this kind of position.



If there were no kos or super kos, then you could view territory go as a form of area go, and chilled go as a form of territory go. Then if you won chilled go you would win territory go, and you would also win jigo if you got the last move. And if you won territory go you would win area go, and if you got the last move in jigo in territory go you would also win area go.

If you make them a form of no pass go (so that somebody would have to fill the Japanese dame), then they become different phases of the same game, and you could stop play at the stage of chilled go and score the game. The trouble is, the score at that stage may have fractions. To get integers you have to continue to territory go.

And, as we know, beginner problems aside, kos that are not resolved at the level of territory go can cause rules headaches.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

My understanding of scoring differences between area and territory scoring are that originally, group tax aside, go was scored using territory scoring, with the caveat that both sides had to play an equal number of plays. Passing was not a move, but games ended when players agreed they were done.

In China, it was decided that counting by area was easier to do and was equivalent to the old scoring, so this change didn't affect the scores.

In Japan, territory scoring was brought over with go originally, but the rule requiring that both players play equal numbers of stones was at some point lost (similar to the change to an empty board at the beginning from cross-hoshi). You will notice than in the example given, if both players are required to play an equal number of moves, white's last move fills in a point of white's territory, returning to the same result as with area scoring.

AGA-style territory scoring restores the requirement for both players to play an equal number of stones. Incidentally, it also counts eyes in seki, like chinese rules, but that's a different topic.

ppl think that the result will differ by only one point but!
i can give you examples of same game that the result differ by more than 10 points.

correct me if i am wrong... in chinese rule territories in seki can be converted into points.
in japanese rule it is all dame.
as a result it is possible to have different result differ by multiple points.

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

This is true, but situations where there are sekis and one side has more points in eyes in seki than the other seem like they would be pretty rare.

so you'd better be sure which rule set you're using before you start playing.

In this case, "Japanese rules" refers to rules with the concept of perfect hypothetical play. Since this concept relies on arbitrarily great finite or infinite numbers of hypothetical sequences and decisions, not the Japanese rules themselves have worked, but the illusion of approximating them by verbal means.



In this case, probably "Japanese rules" refers to a Western verbal approximisation ("verbal Japanese rules"), which does not or not as seriously care about the concept of perfect hypothetical play. So if you did not meet beginners with difficulties to understand such rules or tournament players insisting on (too) strict rules application, your experience has been possible for you.



Citing Thatcher: "No, no, no, no!" The core of the debate is the insistance of professional style Japanese rules with their concept of perfect hypothetical play and its arbitrarily great finite or infinite numbers of hypothetical sequences and decisions. They happen for EACH game end position (regardless of whether the players mention or forgo them in practice).

Robert, go is an oriental game. You really need to stop thinking of it with an occidental mentality. You lose most of the fascination with it when you do that. It is like trying to understand Buddhism or Hinduism from a monotheistic point of view.

Slow down and look at the trees instead of spending all your time trying to count the leaves.

_________________
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).

It is interesting that you didn't say a Japanese game. For the AGA to have its own ruleset is in some sense less political than taking sides. We have Japanese, Koreans, Chinese, and others in our tournaments. At least they are all equally confused.

Correct, I did not same Japanese. Oriental culture in general tends to be a little more vague (sometimes much more) than occidental, and that is part of its attraction.

_________________
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).

I think some people underestimate the advantage of being able to count either by territory or area. I have had to use area scoring a few times in tournaments: once, to resolve a dispute with a player who claimed to have won but "misplaced" his captures, and other times with children who absentmindedly throw their captures in my bowl. The fact that in these situations it is possible to resolve the issue without calling a TD is an advantage.

If you don't know how to count by area, learn it. It's good for your soul and you never know when you might need it. You can look at Eddie Kim's video for an example.

Westerners can be plenty vague.

Dumb,

I learned area counting almost 40 years ago. And sure, westerners can be vague, but it is not the primary modus operandi of western culture.

_________________
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).

Oh, I'm sure in your case you did learn area counting. You weren't the audience for that comment. But I've run into too many people who haven't.

I suppose I'm odd in the sense that I liked go before I was interested in any Asian culture. Actually, to be honest, the order I as recall was:

1. Asian women
2. Asian languages
3. Go
4. Asian culture

I'm married now, so I'll downplay #1 on principle at this point, but I'm still working on the last 3. I'm not sure I've seen vagueness as a differentiating characteristic in popular culture at least. Maybe in some areas, like religion, etc. I don't think of RJ as a typical Westerner or a typical anything, so I don't think he's westernizing his approach to go as much as RJifying it.

I don't know whether the "dame polarity" you mention is statistically correct. My personal experience is that it's close enough to a 50-50 chance of who gets the last dame. But your point is good. I think some players see the 7.5 komi used in AGA and think it's high, but they aren't taking to account that maybe half the time white's going to have to give up a net extra prisoner, so it's not as high as it seems...

I developed an aversion to "area scoring" when I was taught it some time ago, and never learnt it properly. I may now have to pick it up....

_________________
Tempus Vincit Omnia

Well at least, I've never ever seen a single Korean discussing or maybe arguing with baduk rules, although a baduk teacher might say,
1. prisoners are your points
2. cannot take ko right after the opponent's take
3. no points in seki
4. draw when a position has to repeat forever, like in multiple kos or eternal life

and what else to complain?


Below is my question separate from above.

So in Area scoring, the score difference must be in odd points, then why should the komi be 7.5 with the point five? Isn't it equivalent in result with komi 8? which seems somewhat more sensible to me.

_________________
Wait, please.

The good news is: just recently, I have discussed about rules with an influential Korean for 3 hours. They are interested not only in Western pairing programs but also in Western input for the sake of correcting their own rules, because they have realised that they cannot solve this problem alone. More later.

Also a good news to me. ^^

_________________
Wait, please.

The difference is odd, except if there is an odd number of shared liberties in seki. E.g. if you have a seki of two groups with one eye each and one shared liberty. The shared liberty counts for neither player, so then the difference is even.

Ing rules do in fact specify the komi as 8, but with the proviso that black wins in case of ties.