The Intrepid wrote:
Let's make a quick calculation of how much the move is worth.
1). A simplified calculation:
- Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . . .
$$ | C C X . .
$$ | 4 2 X . X
$$ | 5 1 X O X
$$ | 3 M O X X
$$ | M M O X O
$$ | M M O O .
$$ | . . . O .
$$ ------------[/go]
Score W = (+5) + (-2) = (+3)
- Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . .
$$ | C C X . .
$$ | C C X . X
$$ | 3 C X O X
$$ | 5 1 O X X
$$ | 4 2 O X O
$$ | M M O O .
$$ | . . . O .
$$ ------------[/go]
Score B = (+2) + (-5) = (-3) (We could have gotten this result by seeing that White and Black stones are symmetrically distributed.)
Thus, the move is worth approximately
Score Difference = Score W - Score B = (+3) - (-3) = (+6)
2). A more rigorous calculation:
- Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . . .
$$ | . . X . .
$$ | . 2 X . X
$$ | . 1 X O X
$$ | 3 . O X X
$$ | . . O X O
$$ | . . O O .
$$ | . . . O .
$$ ------------[/go]
This ends in gote for Black. Thus, both players have 50% to play in the area first.
If White plays first, the result is:
- Click Here To Show Diagram Code
[go]$$Wcm5
$$ | . . . . .
$$ | 2 C X . .
$$ | 1 X X . X
$$ | 3 O X O X
$$ | O M O X X
$$ | M M O X O
$$ | M M O O .
$$ | . . . O .
$$ ------------[/go]
Score WW = +4If Black plays first, the play is again gote:
- Click Here To Show Diagram Code
[go]$$Bcm4
$$ | . . . . .
$$ | . . X . .
$$ | 1 X X . X
$$ | . O X O X
$$ | O . O X X
$$ | . . O X O
$$ | . . O O .
$$ | . . . O .
$$ ------------[/go]
Thus, each player again has 50% chance to be the first one to play the followup.
If White plays first,
- Click Here To Show Diagram Code
[go]$$Wcm5
$$ | . . . . .
$$ | C C X . .
$$ | X X X . X
$$ | 1 O X O X
$$ | O M O X X
$$ | M M O X O
$$ | M M O O .
$$ | . . . O .
$$ ------------[/go]
Score WBW = +3If Black plays first,
- Click Here To Show Diagram Code
[go]$$Bcm6
$$ | . . . . .
$$ | C C X . .
$$ | X X X . X
$$ | 1 O X O X
$$ | O 2 O X X
$$ | M M O X O
$$ | M M O O .
$$ | . . . O .
$$ ------------[/go]
Score WBB = +2Therefore,
Score W = 50% * Score WW + 50% * [50% * Score WBW + 50% * Score Score WBB] = (+2) + 0.5 * [(+1.5) + (+1)] = +3.25
By symmetry,
Score B = (-1) * Score W = -3.25
Therefore,
Score Difference = Score W - Score B = +6.5[/hide]
You were right the first time.
Quote:
- Click Here To Show Diagram Code
[go]$$Bcm4
$$ | . . . . .
$$ | . . X . .
$$ | 1 X X . X
$$ | . O X O X
$$ | O . O X X
$$ | . . O X O
$$ | . . O O .
$$ | . . . O .
$$ ------------[/go]
Thus, each player again has 50% chance to be the first one to play the followup.
- Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . .
$$ | . . X . .
$$ | X X X . X
$$ | 1 O X O X
$$ | O 2 O X X
$$ | . . O X O
$$ | . . O O .
$$ | . . . O .
$$ ------------[/go]
In this position
is sente. We therefore do not say that each player has a 50% chance of playing here first. We regard
as Black's
privilege.
This position is a bit tricky, however, because
in the next diagram is
ambiguous between gote and sente.
- Click Here To Show Diagram Code
[go]$$Bcm4
$$ | . . . . .
$$ | . . X . .
$$ | 1 X X . X
$$ | 2 O X O X
$$ | O . O X X
$$ | . . O X O
$$ | . . O O .
$$ | . . . O .
$$ ------------[/go]
That is, it is not sente, but
gains as much as
. Therefore White can play
, despite Black's privilege. (The point being that if White plays
, Black does not get the chance to raise the local temperature by playing there himself.) Anyway, the exchange,
-
does not change the local count.
Edit: Unhidden.
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The Intrepid
, 
captures a few stones. Suddenly, Uberdude's question makes quite a bit of sense. 
- 
) which could be called looking for a place to resign. Then when Black administered the coup de grace ( 
), White did not resign.