Re: [gnugo-devel] GnuGO 3.4 : moves to consider

[Evan Berggren Daniel]

On Wed, 27 Aug 2003, Emmanuel BERANGER wrote:

> Hello,
>
> I've been playing GNUGO 3.4 recently. (windows version, from Teun Burgers
> site)
> Among the several games I played, I think worth mentionning two of them, in
> which GNUGO made what I would call "braindead tenuki" ...
>
> Other than that, for the kyu player I am, I particularly reckon its ability
> at cutting shapes and kill small groups :-)
>
> Please take a look at moves 181-182 in file 1, and 117-118 in file 2.
>
>
> As an option, one could also consider 199-200 in file 1, but this is less
> of an obvious mistake

These are indeed interesting mistakes for gnugo; thanks for sending them.

In the first error (game 1, move 182) gnugo for some reason believes that
N11 wins the semeai between D8 and L10 (obviously an error); Q5 is the
second highest move at 55 points instead of 88 for N11.

At move 200, gnugo properly understands that Q2 does not save the black
group; it also properly understands that white wins the capturing race
between L10 and Q4.  However, it also thinks that Q2 kills L10 (?!).

The problem in the second one is a problem of the persistent cache; gnugo
reads things earlier in the game, and then fails to update when the board
changes.  If the game is replayed from move 112, gnugo produces the game
move; if given the position without any leadup, it plays H7 (the correct
move).

Thanks

Evan Daniel