Re: [gnugo-devel] Semeai

[SP LEE]

> I just watched gnugo lose a game against TanGo4746.  At move 179, the
> following position came up. Gnu go was white and at the move:
>
>
> Now, my question is: wouldn't it be natural to try the owl defense
> move as the semeai defense move first in any semeai?  Or have I missed
> something?
>
>         -Inge

Here is a game I played with gnugo which should be the similar situation.
  A B C D E F G H J K L M N O P Q R S T
19 . . . . . . . . . . . . . . . . . . . 19
18 . . . . . . . . . . . . . . . . . . . 18
17 . . . X . O . . . O . O . . O O O . . 17
16 . . . X . . . O . X . O X X O X . O . 16
15 . . . . . . . . . . O . O X O X . . . 15
14 . . . . . . . . X X . . O X X . O . . 14
13 . . . X . O . O . X X O . . . X X . . 13
12 . . . . . . . . O O O X O O O O X . . 12
11 . . . . . . . X X O . X X X X . X . . 11     WHITE (O) has captured 2 
stones
10 . . X X . X X . O X X . . . . X . O . 10     BLACK (X) has captured 2 
stones
9 . . . . X O . . O . X . . O . O O . . 9
8 . . . . O X X X O O X O O O . O X X . 8
7 . . X . . O O O O . O X . X X . . . . 7
6 . O X . . . X X O O O X . . . . X . . 6
5 . O X . . . X O . O X X . . . . . . . 5
4 . . O X . . X O O X . X . . . X . . . 4
3 . . O X . X . O X X X O . . X . . . . 3
2 . . O O X . . X . X . . . . . . . . . 2
1 . . . . . . . . . . . . . . . . . . . 1
  A B C D E F G H J K L M N O P Q R S T

Black should connect at Q11. Although the black group doesn't have two clear 
eyes, but it will have have much more liberties than white.

The owl code did find Q11 as a defense move.
 Q11: owl attack/defend for M12
 Q11: 26.78 - change in territory
 Q11: 1.68 - strategic effect on N16
 Q11: 2.29 - strategic bonus for M12
 Q11:   0.00 - total followup value, added 0.00 as territorial followup
 Q11: 0.41 - connects strings (connect value 4, shape factor 0.082)
Move generation values Q11 to 31.16

How ever gnugo started to fill liberty at E7:
 E7: owl attack/defend for J10
 E7: owl attack/defend for M12
 E7: 75.82 - change in territory
 E7:   36.97 - J10 strategic value already counted - B.
 E7:   0.01 - total followup value, added 0.01 as territorial followup
 E7: 0.01 - added due to followup (0.01) and reverse followup values (0.00)
 E7: 0.04 - secondary
 E7: 0.52 - connects strings (connect value 5, shape factor 0.104)
Move generation values E7 to 76.38

Top moves:
1. E7  76.39
2. M9  74.73
3. Q11 31.17
4. P10 31.06
5. H10 27.13
6. H9  26.78
7. F6  25.19
8. S11 12.36
9. B7  10.68
10. Q14 10.64

Of course after white played at Q11, black is short of liberty.

SP Lee

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