On Apr 27, 4:43 am, David Richerby
wrote:
raylopez99 wrote:

No, but popular means not as accurate as a journal paper, which the
original paper was.

Popular does not mean `not as accurate'.

Generally it does, statistically speaking.


Otherwise it's like saying whoever wins this Usenet thread is right
moreso than two chess researchers debating.

It's not like saying that at all. And what's this about `winning'
threads? I'm posting to share information, help people understand
things and hopefully be entertaining from time to time. What are you
posting for?

To win this thread. I win.


[...] the authors are looking for a standardized (normalized) way
of spotting blunders.

Just because they used the same system for everyone doesn't mean
the system was good or useful. [...] You need to apply the same
*good* measure to everyone.

That is the ideal, but my point stands--equally bad is not so bad.

Strongly disagree. Consider an even more ludicrous measu the
better player is the one with most a's in his name. (That said, this
does explain why Lasker beat Steinitz, why Capablanca beat Lasker, why
Alekhine beat Euwe, why Tal and Petrosian beat Botvinnik, why Karpov
kept beating Korchnoi and why Kasparov kept beating Karpov. Perhaps
there's something in this, after all?)

Irrelevant. We are talking about using a chess program not as strong
as the players it rates, to rate the players based on the least number
of tactical mistakes (and the least number of positional mistakes,
since chess programs do make positional evaluations, often
surprisingly good). We are not talking Mensa word games.



And BTW using your example, a player who wins in the middlegame is
indeed probably stronger than one who wins in the endgame

Disagree strongly.

(it's tougher to win a short game--think of winning a chess
brilliancy against equally matched opposition--than to grind out a
win in the endgame.

The scarcity of short games at high level is because short games are
the result of catastrophic mistakes and high-level players tend not to
make those.

Whatever dude. My point stands: winning in the middlegame is tougher
for equally rated players than winning in the endgame. Probably worth
10 centipawns.


-The fact that Riis found positional sacrifices not evaluated by
Crafty is not convincing since: (1) such positional sacrifices are
rare--as computers have shown, chess is largely tactics; (2)
everybody will be judged equally by Crafty, so others pos sacs are
also scored 'badly', so nobody will lose relative standing to one
another

No. A player who plays more positional sacrifices will be
penalized for playing moves that crafty doesn't understand.

No. See my point above.

No, really. A player who makes more moves that Crafty doesn't
understand (e.g., positional sacrifices) will have greater deviation
from Crafty's play than a player who makes only moves that Crafty does
understand. Hence, he will score lower. Not because he plays bad
moves but because he plays moves that are better than the ones Crafty
found.

But this is rare. Remember, chess is 99.7% tactics. Has a decade of
computer chess and Deeper Blue not taught you anything? And you, a
programmer no less?


And chess is 99% tactics (famous quote).

If you're going to argue by quotation, I'll throw in ``82% of
statistics are made up on the spot,'' ``History is more or less bunk''
and ``The devil may quote scripture for his own purposes.'' Oh,
and``I never drink water because of the disgusting things fish do in
it.''

and (3), as long as assumption (1) is valid, Crafty will find the
most "mistake free" chess player, or one that plays closest to
being "tactics mistake free", which is a very good way to
determine a good chess player IMO.

But World Champions make very few tactical mistakes.

Not true. Nearly all games are full of tactical mistakes, except
perhaps at the correspondence chess level. I was reading a book by
John Nunn ("Chess explained move by move") that makes this point in
the preface--Nunn had a hard time finding 20 OTB games that were
'mistake free' for his book, after searching 1000s of games.

I assume you mean ``Understanding Chess Move by Move''? Does he
say that he had a hard time finding games that were mistake free or
free of *tactical* mistakes?

I think he implies both, but since chess is 99.69% tactics, it implies
the latter.


Tal played games that were sound enough that they were very hard to
defeat over the board. I don't think that counts as playing the
man rather than the board.

But on balance Tal was a shock player. Deny that and you become a
chess revisionist.

But, on balance, Tal was a very successful player. As Ron said, the
point is to win, not to play perfect chess.

Tal won, and is a winner. But he was not the strongest player--that
is the player that made the least mistakes. This is routine btw in
computer chess --once a GM, I think it was Walter Browne, was rated to
see how 'closely' he played an ending where the best play is already
known (I think it's the B+N+P database called "Nablom*" something,
pretty famous), just to see how 'close' he played to the (already
known) perfect ending database. THe theory was the stronger the
player, the closer he plays to the 'theoretically correct' perfect
play of the database. Why is this so hard to understand? You
understand pointers don't you, yet can't grasp this? Or perhaps you
still program in Visual Basic and Perl?


In a match of coolheaded Karpov or Kramnik versus Tal, all in their
prime, the less emotional player is likely to win

Hmm... The two Botvinnik-Tal matches between them were only won by
Botvinnik +12-11=19. Hardly a convincing victory for the cool head.

Pace Karpov's lifetime record against Tal, which is way positive. Of
course it was a young Karpov against an older, sick Tal, but the point
stands.

Well, I'm not sure the point does stand. That rider about Tal being
old and sick strikes me as being just a leetle bit significant.

Actually I was wrong. Per another post in this thread the same day I
posted, apparently in the early 1970s Tal was playing better than
Fischer. He had gotten over his serious kidney ailment. So my point
still stands and indeed is stronger than before, like Tal was.


Think of all the bogus moves made by beginners, sacrificing knight
for pawn, "to break up their pawn chain", with no positional
advantage. If you believe chess is positional play more than
tactics then such bogus moves should work more often than they do.
They do not.

This argument is bogus. Sacrificing a knight against one's
opponent's pawn structure is hardly a prime example of `positional
chess'. [...]

Positional chess SACRIFICE was my point. A positional chess
sacrifice is rare in chess is my point (goes to chess being 99%
tactics).

If you meant `positional sacrifices' you should have said that. What
you said was `If you believe chess is positional play more than
tactics.'

Sorry, but now you know what I meant. Move on.


Anyway, I certainly agree with you that tactics are much
more common that positional sacrifices.

Then you conceed my point and indeed the point of Crafty rating chess
players.


But there's an awful lot more
to positional play than positional sacrifices. Indeed, one might say
that ``Positional play is 99% positional-sacrifice--free'' but that's
much less snappy than ``Chess is 99% tactics.''


Whatever. Point being Crafty does both positional and tactical
evaluations, the latter better than the former, but it does both.

Case closed. Like the header says: Greatest chess players ever?
Capa, Kramnik, Karpov, Kasparov, *in that order* (cuz 'puters don't
lie!)

Goodbye, duffer.

RL



Dave.

--
David Richerby Geriatric Laptop Fool (TM): it's likewww.chiark.greenend.org.uk/~davidr/ like an old dumb stripper that you can put on your lap