Important:
Most of the following documents are pdf files (unless otherwise noted).
Here is the
specifications of the current
USCF rating system.
This version, current as of July 2008, recognizes the
discontinuation of half-K events, a new FIDE-to-USCF
formula, and a revised bonus threshold parameter.
The committee developed a set of
approximating formulas
that can be used for paper and pencil updates.
I devised a method to update USCF ratings from FIDE events
that involve players with both USCF and FIDE ratings.
This document, which has
been updated March 10, 2008 (mostly to describe conditions
under which the method is applied) describes
the details of the algorithm.
Here is a scatter plot
along with the current conversion - the figure was produced
by Mike Nolan of the USCF.
In 2003, the Ratings Committee developed the details of a
title and norm system which is
a nearly identical version of the system the committee
offered in 1994 and 1996.
As far as I know, this system is on the queue to be
implemented soon.
In 1998, in response to the title system not being implemented,
the Ratings Committee developed
the life achievement
system which for unclear reasons to me had been shelved.
The feature article
in the October 2006 issue of Chess Life Magazine was an
interview of me (the article is posted here with permission
of the US Chess Federation).
In the November 13, 2006,
Boston Globe, Harold Dondis and Patrick Wolff wrote a
flattering
article about the
Chess Life interview.
The Ratings Committee submitted a
report
to the USCF Executive Board responding to the
ratings proposal by the DDDE committee.
The report was
submitted at the end of September 2000.
A plot showing the distribution
of ratings for players aged 35-45 over the 1990s indicates
that ratings for this arguably stable group have been
generally declining over time.
This may be some evidence that there has been rating deflation.
This analysis was performed by me and Ken Sloan.
Click here for a plot showing
the relationship between USCF rating and frequency of drawn
games. This analysis was based on 1997 USCF data between
established players whose ratings are within 100 points. It seems
to show that the probability of drawing is higher (for
closely rated players) when players' ratings are higher, in
general.
I am the inventor of the Glicko system,
a rating system that extends the Elo's by
incorporating a measure of uncertainty of a player's rating.
If you are considering implementing the system,
you should take a look at my
description of the Glicko
system for details.
If you are interested in the mathematical derivation of the
system, check out my
technical paper on the Glicko
system.
I have invented a new system, called the
Glicko-2
system,
that improves on the original Glicko system.
It is now in the public domain (i.e., you are free to use it).
Some ratings-related research can be found on my
research page.
Mark Glickman (mg -at- bu -dot- edu)
