IGS scoring

[Flint Prophet]

I am VERY new, but I don't understand IGS scoring. When I manually count, it's no where NEAR the score that is given. I'm still learning, but I just played a game where I was fine with how we marked the stones, but the final score was over twice the manual count I did.

To be clear, I'm new and I'm fine losing all the time; I just take exception to how IGS scores things. If anyone has insight, please elucidate me.

Thanks ahead of time,

Flint.

[dfan]

Can you provide an example?

[Mike Novack]

Yes, please provide an example. If you are VERY new the most likely explanation is confusion about which groups are alive or dead.

[Flint Prophet]

MMXFMSAPTC.sgf

(6.02 KiB) Downloaded 833 times

[Flint Prophet]

I tried to post the game, not sure I did it correctly, but it also said it was awaiting approval from a moderator. I might try again...the way I did it was I downloaded the "sgf" and then attached it to the post and put it 'inline' to the post.

[Joaz Banbeck]

This is what the sgf file looks like with the proper tags. Does anyone know what is wrong with it?

[TegaiS]

Hi, IGS says White wins by 121.5 points. How much was your counting?

[Flint Prophet]

White won by 83.5. That's my count.

[TegaiS]

Have you counted prisoners? White has 48 and Black has 7. The difference is 41. The sum 41+83.5 = 124.5 is pretty close.

[RobertJasiek]

After deleting white spaces and all miscellaneous tags, and inserting the SGF file contents explicitly, the SGF appears. So the problem is one of: the white spaces or some missing escape character in the original SGF, or the missing inserting of the SGF file contents explicitly.

[jlt]

For Black, add 1 point for each empty intersection inside Black's territory + 7 captures.

For White, add 1 point for each empty intersection inside White's territory + 2 points for each black stone inside White's territory + 48 captures and subtract 5.5 komi (the game is with reverse komi).

Capture.JPG (92.18 KiB) Viewed 25581 times

[Bill Spight]

121½ points for White looks right to me.


BTW, most go servers do not require it, but it is good practice to fill all the dame, to make sure that nothing is overlooked. Often when the dame get filled or nearly so, big swings can happen and the tables can be turned.

[Flint Prophet]

Okay, I'm still confused, but have been reading a lot...scoring is a lot harder than I first perceived. And so far, I've not read any chapter in a book on scoring that thoroughly educates me (obviously). I will continue to work on it and read this forum which is new to me. I'm 46 years old and a very impatient person, which is one of the reasons that Go appeals to me, because I really want to calm my mind and become a better person.

Thank you all so much for the responses.

[Bill Spight]

Don't worry. You'll get better quickly. After I had been playing for a year in my early twenties, I liked to play over professional games, which were published without all the dame being filled. To my dismay I found that my count sometimes differed from the published result. That is not unusual, BTW.

[Pio2001]

Okay, I'm still confused, but have been reading a lot...scoring is a lot harder than I first perceived. And so far, I've not read any chapter in a book on scoring that thoroughly educates me (obviously).

Hi Flint Prophet,
I understand perfectly how you feel. The rules of go have long been a weak point of this game. So far, the answer to these problems has always been to join a club and have more advanced players explain the matter.

I see, through your games, that you are a beginner. But you have already understood that some stones can no longer avoid being captured, once they are completely surrounded inside an enemy territory.

In order to get a clear version of the scoring rules, use the Chinese (or AGA) rules instead of the Japanese rule.
Here is the text of the French Federation of Go, that use the same kind of rule (translation is mine) :

Territory

A territory is a set of one or several adjacent empty intersections that are sourrounded by stones that are all of the same colour.

End of the game

The game ends when the two players pass consecutively. Points are then counted. Each intersection in the territory of a player brings in one point, as well as each of his stones that is still present on the board.

Besides, starting is an advantage for Black. Therefore, in an even game, White gets compensation points called komi. The komi is usually 7.5 points. The purpose of the half point is to avoid draws.

The winner is the player with most points.

Handicap game

Sometimes, a handicap is given to one of the players, by letting the opponent, who plays Black, playing several moves in a row at the beginning of the game. In this case, White gets half a point (still to avoid draws), and a number of extra points equal to the number of moves that he couldn't play at the beginning of the game.

Notes :
-As long as you can add stones between the territories (example, intersections P4 P5 and P6 in your game), you score additional points (one per stone). These points are called "dame". In practice, that's the main difference with the Japanese rule of go. Under Japanese rules, you can stop playing without filling them. Under Chinese / AGA / British / New Zealand / French rules, you loose points if you let your opponent taking them all while you are yourself passing.

-If you strictly follow the rules, you can see that your territory doesn't belong to you until you have completely captured all the enemy stones that are inside. Otherwise, according to the definition, since the empty intersections are not surrounded by stones of the same colour, these empty intersections are not a territory.
After a few games following the above rules, you will quickly realize that you can predict the score without capturing everything, mentally removing stones that are going to die. That's why all players stop playing before this moment, and, in order to save time, remove dead stones without playing, and count immediately the results.
In the picture posted above, you can see that the software has greyed out these stones.
This shortcut is explicitly allowed in Chinese and AGA rules. It is mandatory in Japanese rules.

-The French rules stated above allow Black to play his handicap stones wherever he wants. This is a French oddity. In Japanese, Chinese and AGA rules, handicap stones must be played on star points in a given order.

-In Chinese rules handicap games, White gets one more compensation point than in French or AGA rules.

-After some time, you will notice that both players stop playing at the same time. The equivalence between counting stones + territory (chinese style), or territory + prisoners (japanese style) will then become clear : since, dead stones and prisoners included, there are (nearly) the same total number of black and white stones, and since replacing a territory point with a stone doesn't change the Chinese score, you can see who's the winner by filling territory with prisoners and just counting the remaining territory.
And that's how the Japanese style of counting (territory minus prisoners) was born.