Score estimator bug

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Numsgil
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Score estimator bug

Post by Numsgil »

I know there are quite a few score estimator bugs, but this one seems especially puzzling.

There's a large seki in the center of the board. If I use the "Scoring" tool, I get a score of something like B+6 (there are prisoners). If I use score estimator, it seems to figure out the correct status of all the stones, but comes up with a score of W+50. :scratch:

See the position at the end of the attached SGF.

Click Here To Show Diagram Code
[go]$$Bc
$$ +---------------------------------------+
$$ | . X O O . . . . O . X . . . . . . . . |
$$ | . X X O . O X . O X X X X X X . . . . |
$$ | . X O O . . O X O O X O O O X O X . . |
$$ | . X X O . O . X . O X X O O O X X . . |
$$ | . . X X O . X . . . O X O . O O O X . |
$$ | . . X O O . X O . O O O X O . X O X . |
$$ | . X X X O . O O . . O O X O . O X . . |
$$ | X X O O X O O X . O . O X O O O X . . |
$$ | X O . O X O X . X . O X X X O X . . . |
$$ | O O O O X O X X . , O O O X X X X . . |
$$ | O X X O X O O O O O O X . O O X . X . |
$$ | . X X X X O X O X O X O O O X X X X X |
$$ | X X O X X X X X X X X O X O O O . O . |
$$ | O O O X . X X X O O X X X X X O O O O |
$$ | X X O O X X X X O O X O X O O O X O X |
$$ | . X X O O O O O O O O O O X X O X X X |
$$ | X . X O . O O X X X X O O O X X X X O |
$$ | . X X X O O . O X . X X X X X . X O . |
$$ | . X X O O . O O O X . . . . . . O . O |
$$ +---------------------------------------+[/go]
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Li Kao
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Re: Score estimator bug

Post by Li Kao »

Sekis never work with SE. If I recall correctly it thinks all stones in a seki are dead and counts them as prisoners.
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Numsgil
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Re: Score estimator bug

Post by Numsgil »

But it graphically marks them as shaded, so it seems to understand the concept.
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Re: Score estimator bug

Post by lefuet »

iirc the score estimator is not improved anymore. the original programmer is gone. the estimator is just left as a convenience for us lazy counters. It still has many bugs but the alternative would be no estimator t all. ;)
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Re: Score estimator bug

Post by Dusk Eagle »

See also this thread. Judging from posts 15-19, I figure the score estimator will never be improved without a complete rewrite (which could be an interesting project).
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Re: Score estimator bug

Post by Harleqin »

The score estimater is a bug. Its results are useless, since you cannot trust them even if they seem right at first glance. Just ignore its existence.
A good system naturally covers all corner cases without further effort.
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Re: Score estimator bug

Post by Numsgil »

Grr, reading that other thread I realize dead end code when I hear it :P

Can we expose a way to override it? For instance, GnuGo can estimate the score. I figure WMS probably wants to keep an all Java client, but exposing a hook to the command line might be a reasonable midstep to a full replacement.
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Re: Score estimator bug

Post by topazg »

You'd need to download the .sgf and load it in a separate window, but I recommend http://ricoh51.free.fr/go/dariusheng.htm very highly with respect to score estimation
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