[computer-go] KO in Hashtable-UCT?

[Erik van der Werf]

On 5/18/07, Chrilly <c.donninger at wavenet.at> wrote:
> When going down a variation the Hash and other Board-State Information like
> e.g. the KO-Point are stored on a stack. Starting from the current Top of
> Stack the detection goes down and search for the same hash-key and Ko-Point.
> Its the "Repeated Position" Detection method of chess. The Gamestack-Pointer
> is decremented by 2, one can stop, when a non-capturing move is done (in
> chess its the other way round).

Non-capturing moves can create repetition (but there will of course be
captures elsewhere in the cycle). Fortunately, there are other simple
criteria. E.g., you can stop whenever a move is played on an
intersection for the first time.

> If a SuperKO occurs, the position is evaluated by the Material-Balance.
> BlackCaptures - WhiteCaptures + Komi.

I guess you mean the *change* in material balance after one cycle. I
don't see why komi should be used here.

> Probably a better way is to ignore the result.

Only for balanced cycles.

Erik