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|Sensory Board Donation|
Chess Scotland is starting a fundraising exercise to buy some new sensory boards for use in tournaments. All sections, from Minor to Open, will get the use of these boards. Discussion on the topic can be found here.
The SJCAET Educational Trust supports young Scottish players, and is a tax-efficient medium for donations to aid the development of Junior Chess. For more details please visit www.scotyouthchess.org.uk.
Chess Scotland Historian Alan McGowan updates the History Archive.
|CS Grading System|
|Calculation Steps for Players who already have a Grade|
An Excel program is available for download here which will replicate the exact calculation steps of CS grading. This user friendly spreadsheet was devised by Alex Clark of Dundee (please note you must have Microsoft Excel).
March 30 2004: Ages in grading list are ages as at midnight Dec 31 in the middle of that grading season.
June 23 2005 (clarification): Junior additions do not apply to ungraded juniors, only to junior players published in the current rating list.
|Maximum Grading Gap and Void Gaps|
The maximum gap between players is set at 400. eg a 1600 plays a 2200. For the 1600 the game is considered as being against a 2000. For the 2200 the game is considered a game against an 1800. If the grading gap is over 735 points the game is void unless the higher player fails to win.
|Minimum Sample Size|
The number of games applied in the grading formula calculations is the actual number of games played or 30 whichever is higher.
No grade is published below 100.
Adults are delisted after completing a fifth inactive year. Players who are still junior (J20 or younger) are delisted in their third inactive year. Players graded 600 and below who are inactive are delisted immediately.
Adult players are given their old grade if it appears in the last five grading lists (the current list is one of the last five). If not in the last five lists then use the last SCA (CS) published grade minus 10 points for every year inactive, prior to the last five eg if you were last published six grading books ago take off 10 points etc. (In practice returning players seem to go back to their previous best strength quite quickly - perhaps they left less enthusiastic and have refound that enthusiasm). Juniors restart as new players (Tournament organisers should always be told if you have previously held a grade).
If you play a non Scottish opponent the order of priority for which grade is used is 1) Scottish 2) FIDE 3) National. Scottish players resident outside Scotland will be listed provided they play regularly in Scotland - they are delisted as per the rules in the previous paragraphs. Foreign players not resident in Scotland are classed as visitors and are not retained in the grading system unless they play a minimum of two weekend tournaments within a grading season. If a foreign player plays two tournaments the Chess Scotland grading system will allocate them a Chess Scotland grade based on the previous foreign grade calculated against their Scottish results. The foreign player will be given the club code NR to indicate their status as a non-resident foreigner. NR players stay in the Chess Scotland system until they are inactive when they are delisted immediately.
|Games against Ungraded Players|
Most games against ungraded players count for your rating. Before the final grading run all the games of an ungraded player are collated. A temporary grading is calculated for the ungraded player based only on games against published graded players and the new grades of previously ungraded players who have achieved a new grade in the season. To be eligible for a temp rating the ungraded player must have played a minimum 5 games against players with such grades and scored in the range greater than 0 and less than 100%. This temporary rating is retrospectively used as the ungraded players grade in the games records of all the opponents of the ungraded player. Temp ratings are listed in italics on the grading website. The temp rating will be very close in value to the initial new grade of the unrated player. The reason why it may be different is because the unrated player may gain additional games from temporary ratings of ungraded opponents. (April 2005)
|200 Up Rule|
Fast improving players can quickly find that their published grade is out of date and understates their current strength. Opponents of the improving player are victimised because expected scores are calculated against a published grade which has proved to be inaccurate. To quickly boost improving players to a more appropriate level and avoid their opponents unjustly losing grading credit the 200 up rule was invented.
To assist in achieving grading stability the program calculates a performance of all established adults comparing what they scored and what they were expected to score. If the adults score less than expected then a small addition is made to all active grades - if more than expected then a small deduction is made.
|Calculation Steps for an Ungraded Player|
To get a new Chess Scotland Grade an ungraded player must play a minimum of 8 gradeable games in two seasons. A gradeable game is one against a published or temporary grade.
* 1: Average Score = Total Points divided by Total Games Played.
* 2: Average Opposition = Sum of Opponent's Grades divided by Total Games Played.
* 3: The Average Score is converted to a Grading Difference using Table 1.
* 4: An initial estimate is made using the above data.
* 5: All the opponent's grades are compared to the initial estimate and adjusted to be no more than 400 points different from the initial estimate. (This adjustment is necessary since a player could get a distorted first grading by playing 7 very high opponents and 1 game versus a very weak player thereby getting a distorted average opposition). This adjustment will change the Average Opposition from Step 2 above.
* 6: The Grading Difference (from step 3) positive or negative is added to the Average Opposition. The Temporary Grade thus calculated is the value all your opponents get in their player records.
* 7: If the ungraded player has played any ungraded players who gained a temporary grade from step 6 then these temp grades will be added to their player record.
* 7a) If any ungraded player had less than 5 results v graded AND 8 or more results v graded or temps then make another calculation. That calculation will be to create an estimate for this specific group by taking all their games v graded and temps and making a TEMP1A estimate (new name for this special case).
* 7b) Slot the TEMP1A estimates into all the opponent's records.
* 8: Using all the games against published and temp grades calculate new Average Scores and new Average Opposition.
* 9: Repeat the 400 adjustment as per step 5.
* 10:Calculate new grade with grading difference added/subtracted from step 9.