FIDE to USCF Conversion
sd
information from Mark Glickman's site:
he USCF takes the issue of foreign ratings and their conversions very
seriously, because they must of course correctly pair foreign players
in Swiss System Tournaments. Some crazy things were bandied about
here, not by our normal sane (well, semi-sane) posters, but others who
seem less informed and have strong opinions but little experience or
knowledge in the area.
I found first the 2006 conversion:
http://www.glicko.net/ratings/report06.txt
What I think is the relevant text follows:
-------------------------------------------------------
Last Fall, Mike Nolan provided the RC with ratings data on
players who had both FIDE and established USCF ratings, and
who were active tournament players in the past three years.
From this data, we determined a revised conversion formula
from the FIDE rating scale to the USCF scale. The new
conversion is as follows: For FIDE rating below 2200, the converted
USCF rating is the same. For FIDE rating between 2200 and 2600,
the converted USCF rating is FIDE + (FIDE-2200)/8. For FIDE ratings
above 2600, the converted USCF rating is FIDE+50. We have
recommended to the USCF office to begin using these formulas
to impute initial USCF ratings for FIDE players who have not
yet entered USCF events. The RC notes that, based on our
data analyses, the conversion is quite imprecise on an
individual basis. Even though the formula prescribes that
a 2200 FIDE player has a converted USCF rating of 2200,
in reality the range of possible USCF ratings
for FIDE=2200 can be as low as 1800 and as high as 2450.
This is the reason that the conversion formula needs to be
applied with caution, recognizing the imprecision in the
correspondence between the FIDE and USCF scales.
--------------------------------------------------------------------------------
This is the most current from 2008:
------------------------------------------------------------------------------
Related to the preceding task, a new FIDE-to-USCF conversion formula
has
been derived based on the correspondence of USCF and FIDE ratings
among
838 players that have recently published ratings in both systems. The
formula to determine a USCF rating from a FIDE rating is given by
USCF = 720 + 0.625*FIDE if FIDE < 2000
USCF = -350 + 1.16*FIDE if FIDE >= 2000
---------------------------------------------------
Thus it looks to me like a 2200 FIDE is a 2202 USCF (please point out
any math mistakes!)
A 2000 FIDE is a 1970 USCF.
There was a change for youth events in 2009, but nothing else I could
find.
raylopez99
> --------------------------------------------------------------------------- -----
>
> This is the most current from 2008:
>
> --------------------------------------------------------------------------- ---
>
> Related to the preceding task, a new FIDE-to-USCF conversion formula
> has
> been derived based on the correspondence of USCF and FIDE ratings
> among
> 838 players that have recently published ratings in both systems. The
> formula to determine a USCF rating from a FIDE rating is given by
>
> USCF = 720 + 0.625*FIDE if FIDE < 2000
> USCF = -350 + 1.16*FIDE if FIDE >= 2000
>
> ---------------------------------------------------
>
> Thus it looks to me like a 2200 FIDE is a 2202 USCF (please point out
> any math mistakes!)
>
> A 2000 FIDE is a 1970 USCF.
>
> There was a change for youth events in 2009, but nothing else I could
> find.
Too generous for Fide it seems.
Here is what my research found, from before 2008:
"According to the USCF, USCF Elo = ( FIDE Elo * 0.895) + 367."
RL
sd
> Here is what my research found, from before 2008:
>
> "According to the USCF, USCF Elo = ( FIDE Elo * 0.895) + 367."
>
> RL
Yes, and again you are a decade or more behind with your research.
Even then the formula did not hold. It was archaic and based on a very
limited rating pool.
Ed Gaillard and some others noted in 2003 this discrepancy (although
it was known several years before that that conversion was not
working):
http://www.chesskb.com/Uwe/Forum.aspx/chess-analysis/420/number-of-players-at-each-FIDE-rating-level
Text of Ed's post and research follows:
________________________________________________
I don't think this is true anymore. Having a little too much time on
my hands, I downloaded the October FIDE list and October USCF rating
list and tried to identify players who were on both lists.
While I'm sure I missed a few, and probably have a couple of false
matches, I came up with 478 such players, of whom 283 had at least one
FIDE-rated game for the current list (I'll call these the "active"
players").
The average FIDE rating was about 11 points higher (2232 FIDE vs 2221
USCF); among active players, the USCF rating was about 5 points higher
(2250 FIDE vs 2255 USCF).
Players with the highest (over 2400, or over 2300 for active players)
and lowest (under 2000) FIDE ratings tended to have higher USCF
ratings (note that there were very few players with ratings below
2000); in between, FIDE ratings tended to be higher.
I'll include summary tables here. If anyone wants the whole
spreadsheet, email me.
"number" is the number of players in the rating range; difference is
the average FIDE rating minus the average USCF rating for those
players. There was only one player under 1900, so I made the bottom
category 1800-2000.
All players:
FIDE
rating number difference
over 2500 23 -57
2400-2500 30 -49
2300-2400 67 -2
2200-2300 152 25
2100-2200 136 28
2000-2100 61 17
1800-2000 9 -43
total 478 11
Active players:
FIDE
rating number difference
over 2500 20 -67
2400-2500 24 -54
2300-2400 44 -11
2200-2300 84 3
2100-2200 67 21
2000-2100 38 4
1800-2000 6 -31
total 283 -5
--------------
SBD
raylopez99
> On Jul 16, 7:13 am, raylopez99 <raylope...@gmail.com> wrote:
>
> > Here is what my research found, from before 2008:
>
> > "According to the USCF, USCF Elo = ( FIDE Elo * 0.895) + 367."
>
> > RL
>
> Yes, and again you are a decade or more behind with your research.
> Even then the formula did not hold. It was archaic and based on a very
> limited rating pool.
>
> Ed Gaillard and some others noted in 2003 this discrepancy (although
> it was known several years before that that conversion was not
> working):
>
>
> Text of Ed's post and research follows:
>
Did you follow the thread I posted on Blitz Playchess Elo vs Fide OTB
Elo?
If you did, you'd have noted that there's such a statistic called
"correlation", which is a number between zero and one (if you were a
real scientist or doctor, instead of a pretend "Dr.", you'd be well
grounded in statistics and I would not have to be lecturing you now).
Zero means no correlation (though there may be a pattern! Complicated
but ignore that for now). One means high correlation, F(x) = y = x.
I know I just confused you with that.
For this 'research' by "Ed" to be accurate, you'd have to show a high
correlation between the USCF Elo and the Fide Elo. What you say?
It's the same person Ray! But wait--how do you know if that person
maybe started out in Europe, then moved to the USA? In the interim,
that person got stronger. Hence the USCF Elo will "catch up" with the
Fide Elo.
What makes me suspicious about the "Ed" "research" is that there was
inversion--for some Elo levels, Fide Elo > USCF Elo, while for other
levels weaker. This was akin to my *weakly* correlated Playchess
Blitz Elo and Fide Elo numbers, which showed the same phenomena (but
for people rather than Elo levels). When you see such inversions, you
should be suspicious that perhaps there is little, or at best weak,
correlation between the two data sets.
I know this paragraph was taxing for you "Dr." Dowd, but try and read
it slow and maybe get an adult to explain it to you.
I hate to break it to you, but you are a Fide 2000 player = USCF 2125
Elo. Your excessive playing of tournaments with the same cronies in
the Alabama region has inflated your Elo (and your ego). But I was
shocked myself to find I probably am a 1850 USCF Elo player, rather
than the 1950 USCF Elo I assumed, so don't feel so bad.
RL
raylopez99
> I hate to break it to you, but you are a Fide 2000 player = USCF 2125
> Elo. Your excessive playing of tournaments with the same cronies in
> the Alabama region has inflated your Elo (and your ego). But I was
> shocked myself to find I probably am a 1850 USCF Elo player, rather
> than the 1950 USCF Elo I assumed, so don't feel so bad.
>
> RL
Yes, I was substantially right, see the data from the USCF on SBD
below.
Of course it's in your interest to pretend that Fide Elo is the same,
or nearly the same, as USCF Elo, but no matter how much spin you put
on it, this just ain't so. The USCF has ratings inflation of 50 to
125 points.
RL
12484438: STEVEN B DOWD
Current Published
Rating (July Supplement)
Regular Rating 2194 2005-04
(Current floor is 2000)
National Master Certificate Earned in 2001
Highest USCF Norms-Based
Title Earned
(in events since 1991)
1st Category
Show Ratings History Graphs
Show Game Statistics
Quick Rating 2010 2005-04
Correspondence Rating 1957
State AL
Expiration Dt. Life Member
Last Change Dt. 2010-02-16
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raylopez99
This thread has been superceded by this thread here:
http://groups.google.com/group/rec.games.chess.misc/browse_thread/thread/95c4ef35ec1638b5?hl=en#
RL