One last rumination on dynamic komi:
The main objection against introducing dynamic komi is that it ignores the true
goal
of winning by half a point. The power of the win/loss step function as scoring
function underscores
the validity of this critique. And yet, the current behaviour of mc bots, when
either leading or trailing by a large margin, resembles random play.
The simple reason for this is that either every move is a win or every move is
a loss.
So from the perspective of securing a win, every move is as good as any other
move.
Humans know how to handle these situations. They try to catch up from behind,
or try to play safely while defending enough of a winning margin.
For a bot, there are some numerical clues when it is missbehaving.
When the calculated win rate is either very high or low and many move
candidates have almost identical win rates, the bot is in coin toss country.
A simple rule would be this: define a minimum value that has to separate the
win rate of the 2 best move candidates.
Do a "normal" search without komi.
If the minimum difference is not reached, do a new a new search with some komi,
but only allow the moves within the minimum value range from the best candidate.
Repeat this with progressively higher komi until the two best candidates are
sufficiently separated.(Or until the win rate is in a defined middle region)
There can be some traps here, a group of moves can all accomplish the same
critical goal.
But I'm sure this can be handled. The main idea is to look for a less ambitious
gloal when the true goal cannot be reached.
(Or a more ambitious goal when it is allready satisfied). By only allowing
moves that are in a statistical tie in the 0 komi search,
it can be assured that short term gain doesn't compromise the long term goal.
Stefan
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