Martin Brown wrote:
David Richerby wrote:
What do you mean by `percentage blunder rate'? The proportion of
the time that the GM plays a move that the engine thinks is, say,
more than one pawn worse than the best move?

That would probably do as a rough working definition. The search
depth or time might also need to be specified.

Sure.


How does that make a difference?

Unforced tactical errors play their part in the outcome of games.
And these are precisely the sorts of thing that computer chess
engines are very good at spotting. Subtle long term structural games
are much harder for them to score.

So you're suggesting that ``Player X makes a one-pawn blunder in n% of
games'' is a better measure than ``Player X, on average scores n cp
lower per move.'' That does sound like a reasonable statement, though
I do worry that sacrifices of pawns are relatively common and might
still be mis-evaluated quite often. Kasparov used to sacrifice a pawn
for long-term initiative faster than you can say, ``My computer thinks
that's a pretty dodgy move.'' :-)

Do you have any guess (or, shock!, data) on how often errors occur in
WC games that an engine (given reasonable time) would score down by
say 100cp?


Dave.

--
David Richerby Swiss Old-Fashioned Atom Bomb (TM):
www.chiark.greenend.org.uk/~davidr/ it's like a weapon of mass destruction
but it's perfect for your grandparents
and made in Switzerland!