The Richter–Veresov Attack (or Veresov Opening ) is a chess opening that begins with the moves:
69-655: It is also often reached by transposition, for example 1.d4 Nf6 2.Nc3 d5 3.Bg5 (the most common move order), 1.d4 Nf6 2.Bg5 d5 3.Nc3, or 1.Nc3 Nf6 2.d4 d5 3.Bg5. The opening was named after the German International Master Kurt Richter and later the Soviet master Gavriil Veresov , who played it frequently for over a quarter of a century. Along with the Trompowsky Attack , Colle System , London System , and Torre Attack ,
138-569: A FIDE rating of 2000 or more. The title can also be acquired by getting a medal in U8, U10, U12, U14, U16 World Youth Championships or Continental and Regional Youth Championships of the women's section as well as by scoring more than 50% points in more than 7 games in the Olympiad. From 2017, direct titles are only awarded as long as a candidate can cross the minimum rating of 1800, however this requirement does not apply for direct WCM titles earned through
207-593: A Grandmaster. It is also possible to become a Grandmaster without ever having been an International Master. Larry Christiansen of the United States (1977), Wang Hao of China, Anish Giri of the Netherlands, Olga Girya of Russia (2021) and former world champions Mikhail Tal of the Soviet Union and Vladimir Kramnik of Russia all became Grandmasters without ever having been IMs. Bobby Fischer of
276-456: A K-factor of 10, which means that the maximum ratings change from a single game is a little less than 10 points. The United States Chess Federation (USCF) uses its own classification of players: The K-factor , in the USCF rating system, can be estimated by dividing 800 by the effective number of games a player's rating is based on ( N e ) plus the number of games the player completed in
345-484: A central advance or direct assault on the enemy king. As a tool for rapid piece development, it resembled a king pawn opening, and required fewer pawn moves than standard queen pawn fare. The opening has never been very popular at the top level, though various prominent players have employed it on occasion. In 1959, for example, David Bronstein played the Richter Attack against Veresov himself. Moving into
414-411: A few points from the higher rated player in the event of a draw. This means that this rating system is self-correcting. Players whose ratings are too low or too high should, in the long run, do better or worse correspondingly than the rating system predicts and thus gain or lose rating points until the ratings reflect their true playing strength. Elo ratings are comparative only, and are valid only within
483-446: A floor of at most 150. There are two ways to achieve higher rating floors other than under the standard scheme presented above. If a player has achieved the rating of Original Life Master, their rating floor is set at 2200. The achievement of this title is unique in that no other recognized USCF title will result in a new floor. For players with ratings below 2000, winning a cash prize of $ 2,000 or more raises that player's rating floor to
552-432: A lower level. If the game ends in a draw, the two players are assumed to have performed at nearly the same level. Elo did not specify exactly how close two performances ought to be to result in a draw as opposed to a win or loss. Actually, there is a probability of a draw that is dependent on the performance differential, so this latter is more of a confidence interval than any deterministic frontier. And while he thought it
621-462: A mix of national federations. The title may also be awarded directly without going through the usual norm requirements in a few high-level tournaments, provided the player has a FIDE rating of over 2300. These include: Beginning with Nona Gaprindashvili in 1978, a number of women have earned the GM title. Since about 2000, most of the top 10 women have held the GM title. This should not be confused with
690-646: A perception that the ratings are fair. The USCF implemented Elo's suggestions in 1960, and the system quickly gained recognition as being both fairer and more accurate than the Harkness rating system . Elo's system was adopted by the World Chess Federation (FIDE) in 1970. Elo described his work in detail in The Rating of Chessplayers, Past and Present , first published in 1978. Subsequent statistical tests have suggested that chess performance
759-403: A player who won more games than expected would be adjusted upward, while those of a player who won fewer than expected would be adjusted downward. Moreover, that adjustment was to be in linear proportion to the number of wins by which the player had exceeded or fallen short of their expected number. From a modern perspective, Elo's simplifying assumptions are not necessary because computing power
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#1732791044425828-565: A player with an Elo rating of 1000, If you beat two players with Elo ratings of 1000, If you draw, This is a simplification, but it offers an easy way to get an estimate of PR (performance rating). FIDE , however, calculates performance rating by means of the formula performance rating = average of opponents' ratings + d p , {\displaystyle {\text{performance rating}}={\text{average of opponents' ratings}}+d_{p},} where "rating difference" d p {\displaystyle d_{p}}
897-454: A prescribed level of achievement in tournaments at classical time controls under FIDE-approved conditions. The title Grandmaster is awarded to outstanding chess players by FIDE. Apart from World Champion , Grandmaster is the highest title a chess player can attain. In chess literature it is usually abbreviated to GM. The abbreviation IGM for "International Grandmaster" is occasionally seen, usually in older literature. The usual way to obtain
966-410: A rating of 1500 and Elo suggested scaling ratings so that a difference of 200 rating points in chess would mean that the stronger player has an expected score of approximately 0.75. A player's expected score is their probability of winning plus half their probability of drawing. Thus, an expected score of 0.75 could represent a 75% chance of winning, 25% chance of losing, and 0% chance of drawing. On
1035-587: A strong chess player was initially used informally. From the late 19th century and onwards, various national chess federations began to draw up formal requirements for the use of such a title. The term "Grandmaster", in the form of a calque from German Großmeister , was a formal title in the Soviet Union, and had also been in informal use for the world's elite players for several decades before its institution by FIDE in 1950. FIDE's first titles were awarded in 1950 and consisted of 27 Grandmasters , 94 International Masters , and 17 Woman International Masters , known at
1104-437: A system based on statistical estimation. Rating systems for many sports award points in accordance with subjective evaluations of the 'greatness' of certain achievements. For example, winning an important golf tournament might be worth an arbitrarily chosen five times as many points as winning a lesser tournament. A statistical endeavor, by contrast, uses a model that relates the game results to underlying variables representing
1173-458: A tournament ( m ). The USCF maintains an absolute rating floor of 100 for all ratings. Thus, no member can have a rating below 100, no matter their performance at USCF-sanctioned events. However, players can have higher individual absolute rating floors, calculated using the following formula: where N W {\displaystyle N_{W}} is the number of rated games won, N D {\displaystyle N_{D}}
1242-457: A unique implementation, and none of them follows Elo's original suggestions precisely. Instead one may refer to the organization granting the rating. For example: "As of April 2018, Tatev Abrahamyan had a FIDE rating of 2366 and a USCF rating of 2473." The Elo ratings of these various organizations are not always directly comparable, since Elo ratings measure the results within a closed pool of players rather than absolute skill. For top players,
1311-403: A whole chapter of his book of best games. Some theoreticians refer to the opening as the Richter Attack. It was Gavriil Veresov, however, who greatly strengthened both the theory and practice of the opening from World War II to his heyday in the 1950s and 1960s. He is credited with demonstrating that the opening contained more subtlety and depth than was previously considered, often culminating in
1380-768: Is Grandmaster (GM). Titles generally require a combination of Elo rating and norms (performance benchmarks in competitions including other titled players). Once awarded, titles are held for life except in cases of fraud or cheating . Open titles may be earned by all players, while women's titles are restricted to female players. Many strong female players hold both open and women's titles. FIDE also awards titles for arbiters, organizers and trainers. Titles for correspondence chess , chess problem composition and chess problem solving are no longer administered by FIDE. A chess title, usually in an abbreviated form, may be used as an honorific . For example, Viswanathan Anand may be styled as " GM Viswanathan Anand". The term "master" for
1449-421: Is a hypothetical rating that would result from the games of a single event only. Some chess organizations use the "algorithm of 400" to calculate performance rating. According to this algorithm, performance rating for an event is calculated in the following way: Example: 2 wins (opponents w & x ), 2 losses (opponents y & z ) This can be expressed by the following formula: Example: If you beat
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#17327910444251518-538: Is a method for calculating the relative skill levels of players in zero-sum games such as chess or esports . It is named after its creator Arpad Elo , a Hungarian-American physics professor. The Elo system was invented as an improved chess-rating system over the previously used Harkness system , but is also used as a rating system in association football (soccer) , American football , baseball , basketball , pool , various board games and esports , and, more recently, large language models . The difference in
1587-475: Is achieved by a series of 150 bullet games, 100 blitz games or 50 rapid games with a performance rating of over 1700. Arena FIDE Master (AFM) is achieved by a series of 150 bullet games, 100 blitz games or 50 rapid games with a performance rating of over 1400. Arena Candidate Master (ACM) is achieved by a series of 150 bullet games, 100 blitz games or 50 rapid games with a performance rating of over 1100. Arena titles can be achieved on FIDE Online Arena ,
1656-410: Is almost certainly not distributed as a normal distribution , as weaker players have greater winning chances than Elo's model predicts. In paired comparison data, there is often very little practical difference in whether it is assumed that the differences in players' strengths are normally or logistically distributed. Mathematically, however, the logistic function is more convenient to work with than
1725-518: Is awarded to strong chess players who are below the level of grandmaster. Instituted along with the Grandmaster title in 1950, it is usually abbreviated as IM in chess literature. Like the grandmaster title, the usual way to obtain the title is to achieve three required title norms over 27 or more games and a FIDE rating of 2400 or more. In general, an IM norm is defined as a performance rating of at least 2450 over 9 or more games. In addition,
1794-426: Is based on a player's tournament percentage score p {\displaystyle p} , which is then used as the key in a lookup table where p {\displaystyle p} is simply the number of points scored divided by the number of games played. Note that, in case of a perfect or no score d p {\displaystyle d_{p}} is 800. FIDE updates its ratings list at
1863-442: Is calculated by taking the player's peak established rating, subtracting 200 points, and then rounding down to the nearest rating floor. For example, a player who has reached a peak rating of 1464 would have a rating floor of 1464 − 200 = 1264 , which would be rounded down to 1200. Under this scheme, only Class C players and above are capable of having a higher rating floor than their absolute player rating. All other players would have
1932-430: Is defined as 200 points, the standard deviation σ' of the differences in performances becomes σ√2 or 282.84. The z value of a difference then is D / 282.84 . This will then divide the area under the curve into two parts, the larger giving P for the higher rated player and the smaller giving P for the lower rated player. For example, let D = 160 . Then z = 160 / 282.84 = .566 . The table gives .7143 and .2857 as
2001-508: Is inexpensive and widely available. Several people, most notably Mark Glickman , have proposed using more sophisticated statistical machinery to estimate the same variables. On the other hand, the computational simplicity of the Elo system has proven to be one of its greatest assets. With the aid of a pocket calculator, an informed chess competitor can calculate to within one point what their next officially published rating will be, which helps promote
2070-414: Is necessary because chess performance in the above sense is still not measurable. One cannot look at a sequence of moves and derive a number to represent that player's skill. Performance can only be inferred from wins, draws, and losses. Therefore, a player who wins a game is assumed to have performed at a higher level than the opponent for that game. Conversely, a losing player is assumed to have performed at
2139-424: Is not measured absolutely; it is inferred from wins, losses, and draws against other players. Players' ratings depend on the ratings of their opponents and the results scored against them. The difference in rating between two players determines an estimate for the expected score between them. Both the average and the spread of ratings can be arbitrarily chosen. The USCF initially aimed for an average club player to have
Richter–Veresov Attack - Misplaced Pages Continue
2208-558: Is often used to mean a player's chess rating as calculated by FIDE. However, this usage may be confusing or misleading because Elo's general ideas have been adopted by many organizations, including the USCF (before FIDE), many other national chess federations, the short-lived Professional Chess Association (PCA), and online chess servers including the Internet Chess Club (ICC), Free Internet Chess Server (FICS), Lichess , Chess.com , and Yahoo! Games. Each organization has
2277-457: Is the highest-ranking chess title restricted to women. FIDE introduced the WGM title in 1976, joining the previously introduced lower-ranking title, Woman International Master. The usual way to obtain the WGM title is similar to the open titles, where a FIDE rating of 2300 and three norms of 2400 performance rating is required against opponents who are higher rated than 2130 on average. The winner of
2346-417: Is the number of rated games drawn, and N R {\displaystyle N_{R}} is the number of events in which the player completed three or more rated games. Higher rating floors exist for experienced players who have achieved significant ratings. Such higher rating floors exist, starting at ratings of 1200 in 100-point increments up to 2100 (1200, 1300, 1400, ..., 2100). A rating floor
2415-523: The Woman Grandmaster (WGM) title. At 12 years, 4 months and 25 days, Abhimanyu Mishra became the youngest person ever to qualify for the Grandmaster title in July 2021. The record was previously held by Sergey Karjakin at 12 years, 7 months for 19 years, Judit Polgár at 15 years and 4 months, and Bobby Fischer at 15 years, 6 months and 1 day for 33 years. The title International Master
2484-564: The World Girls Junior Championship and some other tournaments like Women's Continental Championship is automatically awarded the WGM title. From 2017, the direct titles are only awarded as long as she can reach the minimum FIDE rating of 2100. The current regulations can be found in the FIDE handbook. Woman International Master is next to the highest-ranking title given by FIDE exclusively to women. FIDE first awarded
2553-508: The "Live" No. 1 ranking. The unofficial live ratings of players over 2700 were published and maintained by Hans Arild Runde at the Live Rating website until August 2011. Another website, 2700chess.com , has been maintained since May 2011 by Artiom Tsepotan , which covers the top 100 players as well as the top 50 female players. Rating changes can be calculated manually by using the FIDE ratings change calculator. All top players have
2622-626: The Black reply 3...Bf5, Richter usually continued 4.f3, intending to build a large pawn centre ; Veresov, on the other hand, usually played 4.Bxf6, damaging the black pawn structure. Today, these two lines are known, respectively, as the Richter Variation and Veresov Variation. Bibliography International Master FIDE titles are awarded by the international chess governing body FIDE ( Fédération Internationale des Échecs ) for outstanding performance. The highest such title
2691-628: The FM title is Alekhine Nouri from Philippines who was awarded the title after winning the 14th ASEAN Age Group Chess Championships 2013 in Thailand at age seven. The youngest player to gain the FM title by achieving an Elo rating of 2300 is Faustino Oro from Argentina who, when he was nine, hit 2314 Elo rating after participating in the ITT Ajedrez Martelli Jovenes Talentos 2023. Introduced in 2002 along with WCM,
2760-454: The Olympiad. Arena titles can be earned online using FIDE's server, and are intended for players in the lower rating band. Should a player with an arena title gain an over the board FIDE title, this title replaces their arena title. Arena Grandmaster (AGM) is the highest online title. It is achieved by a series of 150 bullet games, 100 blitz games or 50 rapid games with a performance rating of over 2000. Arena International Master (AIM)
2829-534: The Richter–Veresov Attack is one of the more common branches of the Queen's Pawn Game . The Richter–Veresov Attack looks like the more popular Ruy Lopez opening mirrored on the queenside , but the dynamics of play are quite different. The Encyclopaedia of Chess Openings code for the Richter–Veresov Attack is D01. The opening dates back as far as the game Marshall – Wolf , Monte Carlo 1902. However, it
Richter–Veresov Attack - Misplaced Pages Continue
2898-501: The United States attained both titles solely by virtue of qualifying for the 1958 Interzonal (IM title) and 1959 Candidates Tournament (GM title), only incidentally becoming IM before GM. The more usual path is first to become an IM, then move on to the GM level. At 10 years, 8 months, and 16 days, Faustino Oro of Argentina became the youngest-ever person to qualify for the IM title in 2024. Introduced in 1978 along with WFM, FM ranks below
2967-574: The WIM title (formerly called International Woman Master, or IWM) in 1950. The usual way to obtain the WIM title is similar to the open titles, where a FIDE rating of 2200 and three norms of 2250 performance rating is required against opponents who are higher rated than 2030 on average. The runners-up in the World Girls Junior Championship , the U18 and U16 World Youth Champions as well Continental Championship medalists and U18 Continental and Regional Champions of
3036-470: The ability of each player. Elo's central assumption was that the chess performance of each player in each game is a normally distributed random variable . Although a player might perform significantly better or worse from one game to the next, Elo assumed that the mean value of the performances of any given player changes only slowly over time. Elo thought of a player's true skill as the mean of that player's performance random variable. A further assumption
3105-450: The areas of the two portions under the curve. These probabilities are rounded to two figures in table 2.11. The table is actually built with standard deviation 200(10/7) as an approximation for 200√2 . The normal and logistic distributions are, in a way, arbitrary points in a spectrum of distributions which would work well. In practice, both of these distributions work very well for a number of different games. The phrase "Elo rating"
3174-576: The beginning of each month. In contrast, the unofficial "Live ratings" calculate the change in players' ratings after every game. These Live ratings are based on the previously published FIDE ratings, so a player's Live rating is intended to correspond to what the FIDE rating would be if FIDE were to issue a new list that day. Although Live ratings are unofficial, interest arose in Live ratings in August/September 2008 when five different players took
3243-400: The closest 100-point level that would have disqualified the player for participation in the tournament. For example, if a player won $ 4,000 in a 1750-and-under tournament, they would now have a rating floor of 1800. Pairwise comparisons form the basis of the Elo rating methodology. Elo made references to the papers of Good, David, Trawinski and David, and Buhlman and Huber. Performance
3312-468: The field must have an average rating of at least 2230, must include at least three International Masters or Grandmasters, and must include players from a mix of national federations. There are also several ways the IM title can be awarded directly without going through the usual norm process, provided the player has a rating of at least 2200. From July 2017, these are as follows: After becoming an IM, most professional players set their next goal to becoming
3381-519: The last third of the 20th century, grandmasters of the calibre of Spassky , Tal , Smyslov , Larsen , and Bronstein all experimented with the Veresov Opening as an occasional surprise weapon. Even Karpov employed it with success against Romanishin in a Soviet Team Championship. Other, more frequent practitioners have included Héctor Rossetto , Lev Alburt , Victor Ciocaltea , Nikola Padevsky , and Tony Miles . In more contemporary play,
3450-510: The most important rating is their FIDE rating. FIDE has issued the following lists: The following analysis of the July 2015 FIDE rating list gives a rough impression of what a given FIDE rating means in terms of world ranking: The highest ever FIDE rating was 2882, which Magnus Carlsen had on the May 2014 list. A list of the highest-rated players ever is at Comparison of top chess players throughout history . Performance rating or special rating
3519-517: The normal distribution. FIDE continues to use the rating difference table as proposed by Elo. The development of the Percentage Expectancy Table (table 2.11) is described in more detail by Elo as follows: The normal probabilities may be taken directly from the standard tables of the areas under the normal curve when the difference in rating is expressed as a z score. Since the standard deviation σ of individual performances
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#17327910444253588-490: The official FIDE online gaming platform. FIDE also awards titles for arbiters, trainers, and organizers. The arbiter titles are International Arbiter (IA) and FIDE Arbiter (FA). The trainer titles (in descending order of expertise) are FIDE Senior Trainer (FST), FIDE Trainer (FT), FIDE Instructor (FI), National Instructor (NI), and Developmental Instructor (DI). The organizer title is FIDE International Organizer (FIO). Elo rating system The Elo rating system
3657-442: The other extreme it could represent a 50% chance of winning, 0% chance of losing, and 50% chance of drawing. The probability of drawing, as opposed to having a decisive result, is not specified in the Elo system. Instead, a draw is considered half a win and half a loss. In practice, since the true strength of each player is unknown, the expected scores are calculated using the player's current ratings as follows. If player A has
3726-473: The outcome of rated games played. After every game, the winning player takes points from the losing one. The difference between the ratings of the winner and loser determines the total number of points gained or lost after a game. If the higher-rated player wins, then only a few rating points will be taken from the lower-rated player. However, if the lower-rated player scores an upset win , many rating points will be transferred. The lower-rated player will also gain
3795-649: The rating pool in which they were calculated, rather than being an absolute measure of a player's strength. While Elo-like systems are widely used in two-player settings, variations have also been applied to multiplayer competitions. Arpad Elo was a chess master and an active participant in the United States Chess Federation (USCF) from its founding in 1939. The USCF used a numerical ratings system devised by Kenneth Harkness to enable members to track their individual progress in terms other than tournament wins and losses. The Harkness system
3864-433: The ratings between two players serves as a predictor of the outcome of a match. Two players with equal ratings who play against each other are expected to score an equal number of wins. A player whose rating is 100 points greater than their opponent's is expected to score 64%; if the difference is 200 points, then the expected score for the stronger player is 76%. A player's Elo rating is a number that may change depending on
3933-422: The requirements for the similarly named open titles. These titles are sometimes criticized by both male and female players, and some female players elect not to take them. For example, Grandmaster Judit Polgár , in keeping with her policy of playing only open competitions, never took a women's title. FIDE strips trans men of any women's titles they might have earned while competing as women. Woman Grandmaster
4002-475: The system has remained popular. Grandmaster Jonny Hector has become an adherent of the Veresov and some interest has also been shown by leading GM Alexander Morozevich . After 3.Bg5 ( diagram ), Black's most popular choices are 3...Nbd7, 3...e6, 3...Bf5, 3...c6, and 3...c5, all potentially leading to different variations. White's plans typically include rapid queenside castling and an early f3 and e4. After
4071-512: The time simply as Woman Masters. FIDE's first grandmasters were: The titles were awarded by a vote of the FIDE Congress before the requirements became more formalized. In 1957, FIDE introduced norms (qualifying standards) for FIDE titles. FIDE introduced a higher women only title, that of Woman Grandmaster (WGM) in 1976. In 1978 the subordinate titles of FIDE Master (FM) and Woman FIDE master (WFM) were introduced, followed in 2002 by
4140-454: The title is to achieve three Grandmaster-level performances (called norms ), along with a FIDE rating of 2500 or more. The precise definition of a GM norm is complex and has frequently been amended, but in general a grandmaster norm is defined as a performance rating of at least 2600 over 9 or more rounds. In addition, the field must have an average rating of at least 2380, must include at least three grandmasters, and must include players from
4209-511: The title of International Master but ahead of Candidate Master. Unlike the Grandmaster and International Master titles, there is no requirement for a player to achieve norms. The usual way for a player to qualify for the FIDE Master title is by achieving an Elo rating of 2300 or more. There are also many ways the title can be gained by players with a rating of at least 2100 but less than 2300; they include: The youngest player to be awarded
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#17327910444254278-454: The title. The U12, U14, U16 Continental and Regional Champions of the women's section are also directly awarded the title. The title can also be acquired by scoring more than 65% points in more than 9 games in the Olympiad. From 2017, direct titles are only awarded as long as a minimum rating of 1900 is achieved. Introduced with CM in 2002, Woman Candidate Master is the lowest-ranking title awarded by FIDE. This title may be achieved by gaining
4347-730: The titles of Candidate Master (CM) and Woman Candidate Master (WCM). Similar titles are awarded by the International Correspondence Chess Federation , and by the World Federation for Chess Composition for both composing and solving chess problems . These bodies work in cooperation with FIDE but are now independent of it. The titles of Grandmaster, International Master, FIDE Master and Candidate Master are available to all over-the-board chess players. The requirements for each title have varied over time, but generally require having demonstrated
4416-553: The usual way for a player to qualify for the Candidate Master title is by achieving an Elo rating of 2200 or more. For players rated over 2000 but under 2200, there are many other ways to gain the title; they include: In case a player achieves the CM title through the Olympiad performance, the minimum required rating of 2000 does not apply, after the title regulations update effective from January 1st, 2024. Prior to 2018, there
4485-473: The women's section are directly awarded the title. From 2017, direct titles are only awarded as long as she can cross the minimum rating of 2000. The current regulations can be found in the FIDE handbook. Introduced with FM in 1978, the WFM title may be achieved by gaining a FIDE rating of 2100 or more. The U14 and U12 World Youth Champions as well as U16 and U18 medalists of the women's section are directly awarded
4554-477: Was Savielly Tartakower who played it regularly in the 1920s and even to the end of his life, using it in his victory over Donner at Staunton Centenary 1951. Tartakower's interpretation and treatment of the opening generally led to a closed, manoeuvring game. Kurt Richter was the next player to develop new ideas in the opening, during the 1930s. He mostly found it useful to facilitate his risk-taking style, and he produced some dazzling victories which contributed to
4623-477: Was likely that players might have different standard deviations to their performances, he made a simplifying assumption to the contrary. To simplify computation even further, Elo proposed a straightforward method of estimating the variables in his model (i.e., the true skill of each player). One could calculate relatively easily from tables how many games players would be expected to win based on comparisons of their ratings to those of their opponents. The ratings of
4692-432: Was no minimum rating requirement, and coming in the top three of an U8 continental tournament was acceptable. As a result, there are a number of CMs with far lower ratings than 2000. Though the open FIDE titles are not gender-segregated, the following four titles given by FIDE are exclusive to women and may be held simultaneously with an open title. The requirements for these titles are about 200 Elo rating points lower than
4761-513: Was reasonably fair, but in some circumstances gave rise to ratings many observers considered inaccurate. On behalf of the USCF, Elo devised a new system with a more sound statistical basis. At about the same time, György Karoly and Roger Cook independently developed a system based on the same principles for the New South Wales Chess Association. Elo's system replaced earlier systems of competitive rewards with
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