Life In 19x19

Any idea why SE shows this situation as seki:

Click Here To Show Diagram Code

[go]$$
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . . |
$$ --------------[[/go]

I believe black is unconditionally dead?

dead 100%

Magicwand wrote:dead 100%

So the original question remains, why does SE not recognize it as such? It recognizes IMHO much more complicated situations correctly

what is SE?

Magicwand wrote:what is SE?

Scoring Estimate (in CGoban) - although I'm not sure if it is called exactly that in English client, but I believe I've seen that abbreviation used somewhere.

SE is awesome!

Features:
can kill 2 eyes group. 12d tesuji
can live with not enough space
can make territory with dead marked stones
can create territory with tengen stone

99,99% correct, 12d tesuji + L&D function.
Thousands of people already know: SE is trustworthy. When will you start to trust SE?
: )

tj86430 wrote:Any idea why SE shows this situation as seki:

$$
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . . |
$$ --------------[

Click Here To Show Diagram Code

[go]$$
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . . |
$$ --------------[[/go]

I believe black is unconditionally dead?

The answer is just 'SE isn't very accurate'. It isn't something of bot level complexity, that reads out situations to calculate their life and death status. I don't know what exactly it *does* do, but it will have some simple algorithm that is right a reasonable fraction of the time.

amnal wrote:The answer is just 'SE isn't very accurate'. It isn't something of bot level complexity, that reads out situations to calculate their life and death status. I don't know what exactly it *does* do, but it will have some simple algorithm that is right a reasonable fraction of the time.

Ok. I know that it isn't accurate, but having seen it estimate more complex situations more or less correctly somehow led me to believe it would recognize the basic shapes. Apparently I was wrong.

I think a wider question that could answer all kinds of question about SE would be :

Does anyone know what algorithm SE is using ? Can we find it somewhere ?

IIRC, it wasn't coded by wms.

tj86430 wrote:Any idea why SE shows this situation as seki:

$$
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . . |
$$ --------------[

Click Here To Show Diagram Code

[go]$$
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . . |
$$ --------------[[/go]

I believe black is unconditionally dead?

It is idiotic, but there is an interesting point buried in here. It happens because SE has an incomplete definition of seki.

SE seems to be assuming that a seki exists because each side has 3 common liberties. There are indeed common liberties, and 'having a set of common liberties' is part of the definition of seki. What SE is missing is the part of the definition that continues "...and there are no unused liberties".

The 1-1 point is an unused liberty. In other words, it is a point that either side could use to gain a liberty, and thus possibly break the alleged seki.

Click Here To Show Diagram Code

[go]$$B Black attempts to use the previously unused liberty
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 1 |
$$ . O O X X 2 . |
$$ --------------[[/go]

What does SE think of this position?

Joaz Banbeck wrote:

$$B Black attempts to use the previously unused liberty
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 1 |
$$ . O O X X 2 . |
$$ ---------------

Click Here To Show Diagram Code

[go]$$B Black attempts to use the previously unused liberty
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 1 |
$$ . O O X X 2 . |
$$ ---------------[/go]

What does SE think of this position?

Using the SE used for KGS, it considers that position seki. Along with the following conclusions:

Click Here To Show Diagram Code

[go]$$W Dead.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 1 |
$$ . O O X X . . |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . 1 |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X X O . |
$$ . O O X X . . |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X X . X |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O . |
$$ . O O X . 1 . |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Dead.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 1 |
$$ . O O X . . . |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 2 |
$$ . O O X . 1 . |
$$ ---------------[/go]

Click Here To Show Diagram Code

[go]$$W Seki.
$$ . . . . . . . |
$$ . . . O . O . |
$$ . . . . . . O |
$$ . O . O O O X |
$$ . . O X X X X |
$$ . O X X . O 2 |
$$ . O O X . 1 3 |
$$ ---------------[/go]

Tryphon wrote:I think a wider question that could answer all kinds of question about SE would be :

Does anyone know what algorithm SE is using ? Can we find it somewhere ?

IIRC, it wasn't coded by wms.

I remember a mention of this somewhere. The algorithm itself wasn't posted, but the author was. It was a japanese name.

As for me, ever since I've heard it called that way, I refer to it as the "Score Guesstimator".

Phelan wrote:

Tryphon wrote:I think a wider question that could answer all kinds of question about SE would be :

Does anyone know what algorithm SE is using ? Can we find it somewhere ?

IIRC, it wasn't coded by wms.

I remember a mention of this somewhere. The algorithm itself wasn't posted, but the author was. It was a japanese name.

As for me, ever since I've heard it called that way, I refer to it as the "Score Guesstimator".

Hehe, some affectionately call it "Score Randomizer"

Mef wrote:

Phelan wrote:As for me, ever since I've heard it called that way, I refer to it as the "Score Guesstimator".

Hehe, some affectionately call it "Score Randomizer"

and its even more fun when non-Japanese rules are used -- drives the kibitzers crazy

Yeah, the score estimator was written by a Mr. Yoshikawa. He was a friend of Richard Bozulich's. I met him in Japan and he offered his board evaluation code to KGS, I built the estimator out of it from that.

I do not know how the algorithm works. Several people have looked at the code (I give it away when Mr. Yoshikawa gives me permission to). They all wanted to make small, simple changes (work with non-19x19 boards, let the player say that a group is alive or dead, etc.)...they all ran away screaming when they saw the code. It is very, uhhh, peculiarly, written.