On Apr 26, 5:24 pm, raylopez99 wrote:
On Apr 25, 10:26 pm, help bot wrote:

You know, if you took the games of a typical (1300) rated
player and checked them with a dumbed-down-Crafty (1500),
you might get some useful information, but not nearly as
much as hoped for. But when you take the games of the
world champions and check them with a program which is
short of 2800, you get mainly garbage, combined with many
instances where a tactical oversight is correctly pinpointed.

But chess is 99% tactics help bot.

That old adage is very useful for instructing newbies, but
every world chess champion is competent in this area, so
the multitude of positional misjudgments comes to the fore.


You also penalize those players who *deliberately* chose
to play what they knew to be sub-optimal moves, for
whatever reason. I just did this myself at RedHotPawn,
choosing to grab a Knight rather than leap in with another
piece to set up a 95%-certain mating net. Why? Because
while the mating net was around 95% certain, the capture
of the free piece was 100% certain (unless I have lost my
mind)! When I spot another mating net, things should be
simple enough for me to get the 100% certainty I desire,
and having captured yet another piece, this is all but
inevitable, barring my opponent's resignation.

But you risk the chance of letting your opponent escape--remember the
maxim: "always check, since the next move may be mate".

What you are missing is this: the reason hopping another
Knight into the fracas was not a 100%-certain mate was that
it wasn't a check, but a quiet move. OTOH, capturing the
free piece was a 100% certain massive gain. With my own
King safe, there was virtually no risk of "escape". BTW, I
was not able to execute a mate because my opponent quickly
resigned after giving up (in addition to the free piece) the
exchange to slow me down a bit. He had no counter play
and the material deficit was continuing to mount.


Just recently
I did not follow this move and instead of winning a pawn against my PC
I drifted and eventually lost.

That was *you*. You are a drifter, a patzer, while
I am a "star".


Another item which these statistical analyses overlook
is the deliberate gift of, say, a half-point. These have
been known to occur in world championship level play,
and of course the "nice guys" will be penalized for not
being "tough players", despite clinching the match
with their action.

Keep in mind this was not a statistical analysis of the kind Sonas is
famous for, but a different kind. Also over time the "nice guys"
penalty will statistically average out.

No, it won't. As someone once said: there are nice
guys and there are tough players. The "nice guys" tend
to remain "nice", while the tough players tend to go insane,
getting meaner and even more self-obsessed.


In short, what can be learned is who was least prone
to tactical blunders, and apparently, whose style leans
most toward a sizable gap between what the program
sees as the #1 optimal move, and #2 -- something I
think may be termed the sharpness of play. For one
example, I am playing a game at RedHot now where
I had to decide whether to develop my QB "normally"
via ...d6 and then B-moves somewhere, or fianchetto
via ...b6 and B-b7. It was a toss-up, since it makes
no difference whatever to the outcome. I expect a
computer would see both moves as being nearly
equal, weighing them in such a way as to slightly
favor the move which gives the Bishop immediate
control of squares, though this immediacy is quite
irrelevant to the true value of the moves.

Again, over time this will "wash out" or "average out".

No, it won't. Chess programs are written to penalize
certain aspects while rewarding others (such as mobility,
for instance). There is no averaging-out, but rather the
semi-flaw will manifest itself again and again, ad infinitum.
A chess program is a bit like a doorbell: press it and it
makes the same sound *every time*.

Let me give a little example here. In a game against
GM Petrosian, GM Fischer singled out the move Knight
on f3 to d1 as being one which set the champion apart
from other GMs, making quite a fuss. Of course, a
chess program like crippled-Crafty might very well see
this same move -- many plys beforehand -- as a retreat
which temporarily gives up control of the vital central
squares. In other words, a program is crippled by its
inflexibility in terms of depth of search, while a human
is crippled by his inability to "see everything obvious"
all the time.


In general
sharp play is better than just pushing yourself into a passive
position, don't you think?

Sure. Since my goal is to win, I dislike dead positions,
and passive ones tend to drag things out to the point of
boredom. I don't want to win at move 123; I want to win
quickly, or at least as quickly as reasonably possible.


That's what Crafty is looking for--sharp
play. Sharp play = sharp mind bot!

Crippled-Crafty is not capable of accurately assessing
what is the sharpest move in games at that level. For
one thing, the 12-ply cutoff means that in many positions,
the program is not even in the same league as those it
is attempting to assess. However, if in addition to those
12 plys, it adds a bunch more for tactical search
extensions, that would mean it can perhaps do a good
job on just the tactical exchanges. As I understand it,
the stated goal was not to merely judge which world
champions were least prone to gross tactical blunders.
If that had been the stated goal, there would never
have been so much criticism.


I wonder just how much time, and to what depth
the moves were analyzed before scoring them. I
recall that often a player's move may be scored poorly,
but if executed and stepped forward, a program may
change its mind completely about this, suddenly
realizing it had overlooked something.

No, you're talking about "move on opponent's time" feature. The way
the study was done was to analyze each move for a fixed time,

Um, the article I read (by following the links provided here)
stated that the search was cut off at exactly 12 plys. This
is not the same as a fixed-time search at all.


so no "changing of mind",

FYI: in the famous match where world champion
Kasparov lost to Deeper Blue, in one game (at least)
the program sacrificed a pawn for whatever it thought
it saw, but then immediately changed its mind, going
into defensive mode due to the horizon effect. I am
telling you this because Deeper Blue was about a
bazillion times faster than other programs of the time,
and yet it still managed to lose due to a problem
which has plagued computers since the dawn of time.
Crippled-Crafty at 12 plys is hardly immune.


and even if so, each player had the same scoring
applied, so it doesn't really matter (over time).

What you are missing here is that only the games
of the world championships were scrutinized, so for
some, the sample size was quite small. I would
prefer a *large* sample size when making excuses
about how it all evens out in the end.


Besides, have you
noticed that _MOST_ of the time (not always) the best move found by
Fritz or Crafty in the first five seconds is also the best move found
after 60 seconds?

Yes. And this phenomenon is not limited to chess
programs. The same flaw can be found in shallow-
thinking human players, who are unable to improve
on their first guesses no matter how much time they
are given. IMO, the ability to guess well yet also to
improve on one's first guesses is the mark of a good
player. If a computer cannot do this, odds are it is
because it lacks positional understanding.


Because chess is 99% tactics, and often the tactics
are no more than 4 moves deep (most of the time).


You seem to be stuck at the beginner level, where
indeed, chess is 99% tactics, and little else matters.


RL (a 1950 Elo player, so I can speak with some authority).

The world champions have many games which were
decided by tactics, but they also have many where
strategy was the decisive battlefield, and many where
both tactics and strategy played key roles. In view of
this I think it would be wise to at the very least, make
use of the strongest program available, and give it
plenty of time to assess each position. Additionally,
I would like to see as many top-level games as
possible included, including those from tournament
play -- not just world championship matches.

Even if all this were done, it would still be a simple
matter to skewer the idea of determining "the greatest
player of all time" in this manner. I could easily
produce an example where playing a bad move was
not only intentional, but necessary in order to win.
Where a "blunder" is a thousand times more effective
than the "best" move. Where the room is filled with
gossip about a certain player having allowed his
inferior opponent a certain-lock on a draw, but
where they all have to re-figure the pairings when the
actual result is posted.

-- star bot