Various chess rankings
The chess rankings are a natural necessity for the competitive component. Identical scoring systems are used in various federations and projects – ICCF, USCF, FIDE, etc. Public information shows the world the power of sportsmen based on official results. A number of countries use internal ratings for the convenience of determining the best grandmaster. In most cases, the calculation is carried out after tournaments but sometimes after individual matches.
Popular online themed projects like GameKnot or Chess24 use analogous or simplified formulas. Their leadership positions are associated with the most points and corresponding success in the match. Not the last role is played by expectations in the process of confrontation. Therefore, the difference in the strength of opponents is taken into account. If a beginner beats a serious level master, he gets a higher score.
Many calculations have gone through hundreds of years of evolution and complementarity. Each has its own mathematical features.
The idea belongs to Anton Hoesslinger. For decades it has been the most precise instrument of the West German Chess Federation. Later replaced by the Deutsche Wertungszahl and Elo.
New players get high fixed starting numbers. Full ratings are based on the average performance of the participant. If having achieved better than a net draw set of results. Minus the number of percentage points, it is over 50%. For example, 12–4 or 24–8 wins-to-losses is a 75% tournament outcome.
A less positive result is added to the midpoint score of the competition contestants. Thus, in all cases, all duelists are completely recalibrated after all confrontations. Therefore, no more than 50 points from the average are lost or gained per tournament. Unlike other modern, nationally used systems, lower numbers indicate better performance.
USCF: chess rankings
It is a modification of the Elo system. The K coefficient varies and gives a bonus for superiority in the tournament. USCF scores are typically 50–100 points higher than FIDE equivalents.
The formula for calculation:
Rpre is the player’s pre-tournament rating
N is the number of games upon which Rpre is based
M is responsible for completed matchups in event
Ravg – average performance of the opponents
W is the number of wins, and L is the same, but for losses
If the contestant is a beginner, then N = 0 and Rpre = 0. The final result is rounded up to an integer
Bears the name of its creator. Particular popularity spanned the years in the last millennium and several large organizations. For example, US Chess Federation and some other leagues.
The advantage is the processing of all results for each player in the tournament. If the participant gains 50%, then he is assigned the average rating of the event. Excess or shortfall of the indicator 50% changes the base figures but with one caveat. Plus or minus 10 points for each percentage that differs from the midpoint.
A contestant with a rating of 1600 plays 11 rounds and scores 2½–8½ (22.7%). Whereas competitors have an average of 1850. This is 27.3% below 50%, so their new values are 1850 − (10 × 27.3) = 1577.
There are a lot of existing ones and those that have sunk into history. Turkey UKD, Glicko, and others occupy a special place in the modern world. Some of them are completely unique and use special calculation formulas. While other chess rankings improve on the known ones. So the federations will repeatedly replace them with more accurate ones. Memes, jokes and other chess humor can be found on this page.