On Apr 26, 6:26 am, raylopez99 wrote:

- it fails to understand the simple argument of 'normalization'. The
Matej Guid and Ivan Bratko original article pointed out that Crafty
was used since it was open source and could be modified; the stronger
programs are not, but in any event Crafty is hardly a weak tactics
program and the authors are looking for a standardized (normalized)
way of spotting blunders.

But the test crippled Crafty by cutting off the search
at only 12 plys. In a game between two patzers, this
might be a minor flaw, but at the world championship
level, things are not always so simple.

Although this cutting off at a specific ply makes it
possible to duplicate the test on any computer, it may
have been more useful to use a fixed time instead
(provided the time is equal to or greater than the average
time to complete 12 plys).


-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,

No, they aren't. Only in games between patzers is
the intentional sacrifice of material for position "rare".


chess is largely tactics;

True. But not all tactics are visible at a depth of
only 12 plys. Tactics can flow from positional
advantage, with virtually no limit as to depth.


(2) everybody
will be judged equally by Crafty,

Misjudged would be more accurate.



so others pos sacs are also scored
'badly', so nobody will lose relative standing to one another,

Except at random, due to all the errors.



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 not good enough for these guys.

As all the world champions were good at tactics, it
requires a bit of subtlety to differentiate between them.


Now of course the surrebutter (rebuttal to the rebuttal) will be that
players like Tal will score poorly--and indeed they (he) did--but
let's face it, Tal was more of a shock player that relied on playing
the man rather than the board. In a match of coolheaded Karpov or
Kramnik versus Tal, all in their prime, the less emotional player is
likely to win

A silly statement. As we saw, the wild, attacking
style of GK gave GM Karpov a very hard time, except
for their very first match. How was GM Tal, in his
prime, all that different from GM Kasparov?

Another example was the cool, calm, collected
Bobby Fischer, who was overwhelmed by GM Tal in
his prime, and who calmly observed after the fact
that GM Tal's hyper-aggressive play was "unsound".



(unless he loses his cool and loses...haha... think of
Topolov vs Kramnik). Also nobody ever became champion ignoring
tactics.
That is the lesson of chess. 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.

It's not this simple. The world champions are all
competent at tactics, so the differences between
them are more subtle than just "who was the best
tactician".


So, understanding how chess works, and how chess playing computers
work, and having seen Crafty evaluate pretty good myself, I have to
side with the original article.

If you mean the one I think, it was horribly
skewered by a whole slew of critics under
"Reader's Feedback", in addition to all the
points made by the various critics who had
their articles published.

The primary issue is not that computers are
incapable of ranking the world champions by
accuracy, it is that attempting to do this with
a crippled Crafty and just the games from the
world championships is a poor method.

I would have preferred a deeper analysis by
a stronger program of all their important games,
in conjunction with a side-by-side subjective
analysis of the same games by a human GM
who, instead of tweaking the program to suit his
whims/preconceptions, simply comments on
where he thinks the program went astray.

The ideal might be the HAL9000 computer
"discussing" the games and results in plain
English, and giving "his" considered opinion
on the strengths and weaknesses of each of
the world champions, as seen by a program
rated (in the future) 9000 USCF. :D

-- help bot