Quoting Uberdude from his Journal:
Uberdude wrote:Addendum: However, as a warning against treating LZ's word as gospel, if I make it play the book's 1, then kosumi for white (#2) and next moves all top choices it gives black only 45% to continue at 7 as best move (on 1k playouts).
$$B LZ blind spot setup?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O O . a . . . . . . . . . . . . . . |
$$ | . . X O . O . 1 . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . X . X . . . |
$$ | . . . X . X . 3 . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . 2 . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . O . . |
$$ | . . . 4 . . . . . , . . . . . , . . . |
$$ | . . 5 7 . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . O . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$B LZ blind spot setup?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O O . a . . . . . . . . . . . . . . |
$$ | . . X O . O . 1 . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . X . X . . . |
$$ | . . . X . X . 3 . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . 2 . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . O . . |
$$ | . . . 4 . . . . . , . . . . . , . . . |
$$ | . . 5 7 . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . O . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
However, if 7 is placement here it's happy to block (59%) but then if black "unexpectedly" pushes through white drops to 40%. It wants to connect at 6 and sacrifice the corner in a trade for pushing through outside rather than squeeze under and take the small gote life. So it seems like early in this variation LZ was willing to tenuki the checking extension the book recommends, but underestimated the severity of the peep later. Not sure if more playouts would solve this (I'm using network #139 if anyone else wants to try before I get my new computer).
$$Bm7 LZ blind spot?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O O 5 1 2 . . . . . . . . . . . . . |
$$ | . . X O 3 O . X . . . . . . . . . . . |
$$ | . . X , 4 a . . . , . . . X . X . . . |
$$ | . . . X . X . X . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . O . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bm7 LZ blind spot?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O O 5 1 2 . . . . . . . . . . . . . |
$$ | . . X O 3 O . X . . . . . . . . . . . |
$$ | . . X , 4 a . . . , . . . X . X . . . |
$$ | . . . X . X . X . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . O . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
(Emphasis mine.)
IIUC, Monte Carlo Tree Search can overcome this problem in infinite time.
It seems to me that this illustrates a problem with self play. Both you and your opponent probably have the same blind spots, because you are so similar. It's like, using the hill climbing metaphor, you are climbing the same hill. But there are other hills which may be more important in a given position. These other hills indicate other skills. Given enough exploration and enough time, self play will learn those skills. But they may be learned more quickly with adversarial play. That is, instead of playing against a version of yourself, play against a version of a player that has been trained to beat you. An adversary will probe your blind spots.
Now, if your aim is to produce a superhuman player, we have seen that self play from scratch is the most efficient way known to do that. However, if we are climbing a single finite hill we will reach the point of diminishing returns. (I think that happened in chess.) Training adversaries will initially take more time to reach the same level--in chess, 8 hours instead of 4?--, but may take less time to produce robust, well rounded players.
Another idea is to train for known go skills. For instance, train initially on classic go problems with 0 komi. Then train on the whole board with komi. Will the initial training be a help or a hindrance?