Oh dear...where to start?

David Kane wrote:

...
As I said, the number who receive points that way is minimal. I think it is
an odd practice, to say the least, but it's inflationary effect is very small.
Some
of those receiving points that way are the older players who have stopped
playing games in the NWSRS, so it has no effect other than symbolic.
The bump occurs once or twice per year and the number of points added is small.

OK

On the other hand, people playing at their floor pump points into
the system every tournament. Also, the initially imputed rating
is in most cases higher than the USCF - it's changed over the years
and the details have never been clear. But for most age groups its
higher than 50*Age.

That can be seriously wrong for Seniors...

50*Age is probably too low for anyone aged lower than 20.


Also, consider the "bonus point" mechanism for inflating the ratings.
Imagine two identical pools of players, but players in pool A play
twice as frequenctly as those in Pool B. Ratings in Pool A will inflate
faster than those of Pool B. My guess is that our pool is more active
than the USCF Pool.

You are assuming that the net effect of play is inflationary. That's
certainly not the usual starting point for most Elo-based systems.
Unadorned Elo is usually a deflating system. If the bonus point system
you are using is more inflationary than necessary to buck the natural
deflationary pressure, perhaps you need to fix it. In the current
USCF system, the bonus points threshold has been adjusted to be
mildly inflationary, by design. We have a political mandate to
re-inflate ratings to the 1997 standard.


And ratings of players who play more frequently in the NWSRS will
not have the lag that their USCF ratings have.

What lag? USCF events are now rated the same day they are played.

There have
been comic misjustices in tournaments where USCF ratings were used -
e.g. one boy won the "biggest upset" prize every round even though
in the NWSRS system he had the highest rating and was winning
as expected. But his USCF rating was several years old, and
600 points out of date.

Probably because he was playing "rated" chess under a competing system
which reduced his incentive/opportunity to play in USCF-rated events.
It's a bit twisted to discourage USCF play...and then use USCF ratings.


I don't believe trying to align the scales would have any practical
advantages.


Depends on what you mean by "align the scales". Elo points out a need
for a national rating service to attempt to keep the rating scale stable
over time (so that historical comparisons are at least in the right
ballpark).

The same requirement holds for multiple systems at the same time. If
the scales overlap at all, it's nice if "2000" on one scale roughly
matches "2000" on the other scale.

Note that that is NOT the same as saying that every individual should
have his rating adjusted so it's the same in both systems. In fact,
that is the mark of a bad ratings administrator! if a player is active
in both systems, and OTHER means are used to effectively align the
scales, then the player's two ratings should be reasonably close, and
there should be NO NEED to "adjust" one or the other.

Systems which *use* USCF ratings, but which do not submit their events
for USCF rating, are doomed to create these "comic injustices".

--
Kenneth Sloan
Computer and Information Sciences +1-205-932-2213
University of Alabama at Birmingham FAX +1-205-934-5473
Birmingham, AL 35294-1170 http://www.cis.uab.edu/sloan/