The tables below are a bit of bodge numerically and in terms of HTML; they should be readable by text-only browsers like LYNX and graphical ones like Netscape; I try to avoid "enhancements" but Tables is good standard HTML.
BCF | ELO |
---|---|
70 = | 1160 |
75 = | 1200 |
80 = | 1240 |
85 = | 1280 |
90 = | 1320 |
95 = | 1360 |
100 = | 1400 |
105 = | 1440 |
110 = | 1480 |
115 = | 1520 |
120 = | 1560 |
125 = | 1600 |
130 = | 1640 |
135 = | 1680 |
140 = | 1720 |
145 = | 1760 |
150 = | 1800 |
155 = | 1840 |
160 = | 1880 |
165 = | 1920 |
170 = | 1960 |
175 = | 2000 |
180 = | 2040 |
185 = | 2080 |
190 = | 2120 |
195 = | 2160 |
200 = | 2200 |
205 = | 2240 |
210 = | 2280 |
215 = | 2320 |
220 = | 2360 |
225 = | 2400 |
230 = | 2440 |
235 = | 2480 |
240 = | 2520 |
245 = | 2560 |
250 = | 2600 |
255 = | 2640 |
260 = | 2680 |
265 = | 2720 |
270 = | 2760 |
![]() | generated by A Cool Blue Cat c programme |
ELO ratings are more sophisticated, and are based on statisticians' Normal Curve. Assume that the "class interval" (bottom of category A to bottom of category B) is 200 rating points. The distribution of scores of a player against someone their own strength is expected to fit the normal curve (upper graph) and the expected result against a player different to their rating by "x" class intervals follows the normal distribution function (lower graph).
Working out exact ELO scores from statistics tables (or using computers) is possible but not very practical. Fortunately the middle part of the function +- 1.5 class intervals is more or less straight and so you can pretend that it is straight for most purposes (a.k.a 'linear approximation').
So, to work out your rating performance in the ELO system, you can take the average rating of your opposition, work out your expected score, look at your actual score, and see how your rating should be adjusted. [There are some fiddles to cope with new players, but that's the gist of it.]
I was going to launch into the rest but both Arpad Elo and Joe Brooks have put it better than I could (but note that Joe's account has in mind the US context), and of course it is covered in the wonderful FAQ.
Glicko Ratings as implemented on the Free Internet Chess Servers (FICS) contain the fiddles for new players built in to the formulae used, so the same formula can be used by the computer for all players. This is a superb refinement to the ELO system but not readily implemented for pencil-and-paper tournaments.
Most GMs amd IMs come in the 'class' ELO 2400-2600. When Elo wrote, he regarded 2600 as 'World Championship Contenders', although now the term Super-GM is used in magazines (at least in the UK).
The figure that ELo took as the top of "strong amateurs" was 2000 (BCF 175), although clearly many strong amateurs are better than that. The 'magic figure' in this country always seems to me to be 200 BCF (2200 ELO), as you will discover by talking to any UK player whose highest-ever grade is 199. It's the chess four-minute mile here, although you don't get called a master by reaching it.
LEVEL | BCF grades | ELO | USCF class | Eastern European category |
---|---|---|---|---|
{D} Minor | BCF 80-100 | ELO 1240-1400 | D | category 4 |
{C} Intermediate | BCF 100-120 | ELO 1400-1560 | C | category 3 |
{B} Major | BCF 120-150 | ELO 1560-1800 | B | category 2 |
{A} County | BCF 150-180 | ELO 1800-2040 | A | category 1 |
Top county players | BCF 180-200 | ELO 2000-2200 | Expert: USCF 2000-2199 | candidate master |
ELO 2200-2300 | US National Master: USCF 2200-2399 | National Master | ||
ELO 2300-2400 | US Senior Master USCF 2400+ | National Master | ||
International Master | BCF 220-240 | ELO 2360-2520 | ||
Grandmaster | BCF 240-250 | ELO 2520-2600 | ||
Super-GM | BCF 250-270 | ELO 2600-2700+ |
This document (bcftable.html) was last modified on 17th Sep 96 by
Dr. Dave