
A Chess Firewall at Zero? - deweerdt
https://rjlipton.wordpress.com/2016/01/21/a-chess-firewall-at-zero/
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klodolph
I always find it interesting when people say things like "chess is a PSPACE
problem", because in order to define it as such, you have to consider the
board size to be variable, even though it's always 8x8.

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tromp
But you can safely say "Ladders are PSPACE-complete" about the game of Go
which is played on many different sizes, some far larger than the standard
19x19 (e.g. KGS supports 38x38 boards).

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w0bb13
The number of serious games above 19x19 is basically nil, so the difference is
a bit misleading (although it's definitely more common in go).

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hollerith
I'm interested in the topic, but found the exposition hard to follow.

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jasonmp85
Yeah, it leads with a bunch of maybe-related logic history and I'm not really
sure where the thesis starts. Maybe it's just a Monday morning, but the
writing was impenetrable to me (and not because of the topic, but because of
the prose).

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recursive
How do you read the charts? I can't make head or tail.

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tromp
They show number of blunders (score dropping 1.5 or more) categorized by
player strength and current position evaluation according to either Komodo or
Stockfish. The conclusion is that people blunder much more in worse positions,
but they blunder most in dead even positions.

At least I think that's what it says:-)

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rspeer
I'm not following all of the theory involved, but this makes me wonder if the
"firewall" is just an effect of the scale on which they're measuring
positions.

Chess engines evaluate a large range of positions as having value 0.00. In
fact, an omniscient chess engine would evaluate every position as either
having value 0.00 or as being "mate in N" (where N could be unreasonably
large).

So maybe the blunders from positive positions are smaller because, as
evaluated by a sufficiently strong chess engine, they mostly drop you from
+(small number) to 0.

