(Sterten) wrote in rec.games.chess.misc:

I don't see CeeBee's point:
"it's not based on differences alone, so it can't work."

No. You replace a system that is based on differences in strength from
_actual_ play with differences in strenght from a computer benchmark
crudely translated from differences in strenght in actual play. That
doesn't give more "absolute" results, but worse results.

Your logical error is that you still want to translate strength
differences to "more objective values", which mixes up the basic idea of
absolute strength with differences in strength.


Sure it's based on differences, you have to fix
a range.
You can't know how good it works, since
we've not discussed the details yet. If my system just
weight's the result with 1 and the move-quality by an infinitesam
amout, then it's almost equal to the existing
system. These parameters have to be optimised.

If one player permanently looses by time, this will be
taken in account, I don't ignore the result.
But if one player permanently looses on time and played
well, he should get a better rating than a player
who permanently looses on time and playes poorly.
This reflects the expectation of his future perform:
he once might learn how to manage his time-problems.


But you wanted a more absolute rating, and now you introduce the notion
about possible future performance. You suggest that knowing the moves is
enough to be qualified as a good player. This is not the case. If my
opponent -who is as strong as me- thinks longer that me in an actual game,
he finds better solutions, and might win. However the clock prevents him
from doing that. So he loses on time. And now you state that shouldn't be
taken into account, and he's the stronger player.

In that case your system leads to a qualification "ceebee's opponent is
stronger than cee, because he found out better moves in an actual game,
yet not within his allotted time". But if we both stuck to our time, we
would have drawn, because we're equal in strength. The Elo system values
that correctly, your system doesn't.


It's just unreasonable to loose by time permanently,
there is nothing you can do, if someone wants to
outfox the system by playing well but then resigning
or loosing by time.. But that's unreasonable.
It's just rated as a bad move.


suppose there only multi-game matches, no tournaments.
System A only rates the outcome of a match,
which player won. System B also takes in account the
score, so a 10:0 gives more ELO-points than a 5.5:4.5 .
Which system would you prefer ?


Neither of the systems is a correct description of the Elo system. The Elo
system takes into account both individual results _and_ opponent's
strength. A 10:0 victory by Kasparov over a patzer is less worth for his
Elo points than a 5,5:4,5 win in a 2700+ opponent match.



Let me explain in more lenght.

Your idea was:
"The computer analyses the positions and rates every single move of
the game and finally calculates a rating-number for both players
and that game based on the moves rather than the result."


Recapitulating you suggest to replace the current rating system with a
more objective benchmark by computers based om move valuing.

I have explained that the current rating system is not about strength ,
but about strength differences. Even better: this is the prime objective
of the system. Why then are people so convinced that ratings tell you
something about absolute strength?

It's because chess player pools are so fluently intermixing with each
other, both in time as in location. It won't surprise you that a 2200
player from say Australia is often on par with a 2200 player from say
France. Players mix with each other in worldwide tournaments, they mix
with players at home and de facto those players mix with players worldwide
- as a result ratings are often leveled. Older players with rating
established against retired players play younger players and thus transfer
those strength differences from one age pool to the other.

But it does _not_ mean the rating system gives an accurate measure of
strenght.

Differences of the same order just mix throughout pools, but they stay
differences in strength. Often people don't understand that: they want to
compare Fischer with Kasparov. But to no avail: the playing pool of
Fischer is too much disconnected from Kasparov's pool of opponents. Their
rating difference has no meaning.

Sometimes you'll read here that ratings are inflated, because in earlier
day you were a top grandmaster at 2600, while now you have to be 2700 to
be very strong.
Of course this is nonsense, the rating calculation hasn't been changed: a
difference of 200 still means the same in winning/losing chances as 30
years ago. Rating inflation would mean that a bigger difference is needed
to have the same winning chances than in the past. That's only possible if
the calculation method has changed, which isn't the case.

Difference, not absolute strenght.


Now you want to develop a system that values chessplayers on individual
moves. That is not a new idea, but what does it mean? It means you have to
know what is important to be strong. Tactics? Positional knowledge?
Recognition of standard patterns and characteristics? Knowledge of opening
theory? Knowledge of endgames? Knowledge of games from past masters?
Knowledge to not find one crucial move, but calculate the actual and
correct move sequence? The ability to play a game without a losing move
after ten strong moves? Psychological strenght in a game? Physical fitness
during a tournament? The ability to think undisturbed in a noisy room? The
speed at which you solve a problem? The number of games you're able to
play at a constant level?
All these things determine the strenght of a chess player, and even more.

First problem: what is their comparative weight? You suggest that a
computer can tell you better how strong a chess player is in a 20 games
round robin tournament, at fast time controls, in a cold playing arena
with thousand spectators on an uncomfortable chair, against a very strong
and impressive opponent than the Elo-system.
How would that be in a luxurious environment in one's hometown, against a
homesick opponent?

As important is the question of chosing and especially valuing those
moves.
Giving a value to a move is referring to another standard. Which standard
is that? What is the value of move one? And what of move two? Why would
move one be more valuable than move two?

In practice you arrive at determining differences in strenght between
moves. It means you suppose an arbitrary difference is better than a
difference based on actual play. But we want to know strength in actual
play, and not in a theoretical situation.The proof of the pudding is in
the eating, not in knowing the recepy by heart.

Weird but true, but there is a system for just that: the Elo-system. Your
computer system doesn't do that. It can give you a player that scores
better than Kasparov yet loses every game against him. Put them both back
around your computer test and the results will be the same: your player
is better in the computer test than Kasparov. And worse, your system has
no way of dealing with that discrepancy.

But not with the current rating system you consider inferior: that system
takes into account evey win and loss. In the above example, your tested
player will see his rating drop rapidly below that of Kasparov, and _that_
tells you even more about his actual strenght than your benchmark. And
that while the Elo system wasn't even developed for that purpose.

You made two error in your idea: first of all you consider the current
rating system as a system to determine strength, which is not true, and
secondly you suppose that a computer valued rating without a pool of peers
and without proper understanding of all determining factors can give
_better_ information than the current rating system.

Maybe one day we will be able to establish all factors defining absolute
strength, but the current batch of computer programs is certainly no match
for the well estabshed and proven Elo rating system.

--
CeeBee


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