[weiqi rules] The difference between area and territory scoring.

With many teachers and pro players, the answer of the title is "almost same". I respect these opinions, but in fact, these two method have differences in result or playing.

1. The difference of result

[Black player to go last move]

To simplify, we use 9x9 board.

The game is finish.








If we use territory scoring (Japanese rules). black 31 point, white 30 point, b wins without komi.





It's easy to change to area scoring(Chinese rules).
Just add the stones (marked), each (black and white) have 10 stones on the board. black 31+10, white 30+10, B wins.




The problem is what if the game final like this.




Black go last move (marked 1), Japanese rules: black 30 point, white 30 point, even game without komi.




But use Chinese rules are different, Black wins with 1 stone. Black 41 stones, white 40 stones, black wins.
In Chinese rules, if the black player to go last move, sometimes it may add 1 stones to black. To equal black and white, the last move should be half to each others. But the Chinese rules gave the half stone to black. There's few game in history that black players use this advantage to win the game.

[Seki with eyes]
In Japanese rules, no count the eyes in seki. The reason is simple, if both decide to end the game, black and white can have 1/2 empty nodes.

This is seki.




In Chinese rules, black and white each have 1 stone at marked place. And the middle place gave to b and w 0.5 stones each.
In Japanese rules, no count to marked place.




In Japanese rules, no count, even it looks like the white have 2 points.





In Japanese rules, no count, even it looks like the white have "a lot" points. this game black wins 2 points.
In Chinese rules, Black lose with 31 stones.(black 41 stones to win the game.)



2. The difference when playing

[Bothering]
In this game, after black pass, The white is afraid to bother black's territory in Japanese rules.


Black pass, there's no dead stones when playing.





White have to consider that need to go marked 1 or not. Because in Japanese rules, if white goes and black still pass, the marked 1 should be a dead stone, white will lose 1 point of territory. But if it's in Chinese rules, just go, even it is dead, the result will not change.Pro players may think this is stupid, live or die, win or lose are all on the board. Why we need to consider to go or not to go?
To the beginners, or even the players over 1d, the players are tend to capture stone when playing, less to think pass or not. Of corse we need to learn "when" to pass, but if it is not against the rules, no one can stop anyone to go to others territory.
These year the championships are reduce the play time. It may cause no enough time to count territory when playing. What if there's a "free" chance to try to live in others territory, why not?
On the contract, when white go to black's territory. In Japanese rules, black needs to consider to go kill or not, if pass, win a point (white marked 1 need to set back to his territory when end of game.) But if black pass, can anyone be sure that white will not live in territory? It feels a lot of fun here, but the Chinese rules canceled it.



3. Dispute

[To be sure the dead]


Game finished, white wins, black dead at right below corner.





But black think it's not dead, and white is dead inside.





So if white need to sure that black is dead, need to kill black. But it will reduce a lot of territory. Chinese rule will not effect the result, just go kill it.

Example:

Once of the time, I judged a game with 2 beginner kids. 

At the end of game, white said: "My teacher said, after I put in the middle, this become a dead 5 corner, let take out these blacks." But the Black said that it was alive. 

They called me to judge. Fortunately, we use area scoring (Chinese rules) in Taiwan. I told the white to kill the black to prove it's death.

But the white gave wrong move!

After black ate the white stones.

It became alive. White lost the game.

White kid cried loud, and I feel bad. Did I judge wrong? I told the white kid to ask his teacher after put in the middle, how to kill in the end. And maybe the white kid will learn all the reason. In territory scoring(Japanese rule), We just point out black is dead, don't need to learn why. To know it's dead is good enough. To my opinion, Chinese rules is better in this situation.

There's few dispute, such like corner twist 4, 3 point if you just put it there. (sorry about my poor English.) I will discuss in future.

Have fun!