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Elo in Snooker??

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In the introduction it is claimed that the elo rating system is used as a rating system in snooker (amongst others). I have removed that until someone can provide a source for that. For me it's just plain wrong. The Snooker World Rankings are based on the prize money won within the last 2 years ("Rankings FAQ - WPBSA".), i.e. where your rating is based on how far you've come in tournaments, and not on the outcome of individual games and the rating of the opponent.

Figure 2

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shouldn't the solid and the dotted black lines be the other way around in figure 2? CwelTHC (talk) 17:11, 1 May 2023 (UTC)[reply]

or rather the rating change values be flipped around to account for greater changes in unexpected outcomes CwelTHC (talk) 17:14, 1 May 2023 (UTC)[reply]
by "figure 2" i guess you mean the one with caption beginning "Graphs of probabilities and Elo rating changes…"? —Tamfang (talk) 20:58, 21 May 2023 (UTC)[reply]

The development of the Percentage Expectancy Table

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   D        P    |    D       P    |    D        P
Rtg.Dif   H   L  | Rtg Dif  H   L  | Rtg Dif   H   L   
  0-3    .50 .50 | 122-129 .67 .33 | 279-290  .84 .16 
  4-10   .51 .49 | 130-137 .68 .32 | 291-302  .85 .15  
 11-17   .52 .48 | 138-145 .69 .31 | 303-315  .86 .14  
 18-25   .53 .47 | 146-153 .70 .30 | 316-328  .87 .13  
 
 26-32   .54 .46 | 154-162 .71 .29 | 329-344  .88 .12    
 33-39   .55 .45 | 163-170 .72 .28 | 345-357  .89 .11   
 40-46   .56 .44 | 171-179 .73 .27 | 358-374  .90 .10   
 47-53   .57 .43 | 180-188 .74 .26 | 375-391  .91 .09
 
 54-61   .58 .42 | 189-197 .75 .25 | 392-411  .92 .08   
 62-68   .59 .41 | 198-206 .76 .24 | 412-432  .93 .07    
 69-76   .60 .40 | 207-215 .77 .23 | 433-456  .94 .06    
 77-83   .61 .39 | 216-225 .78 .22 | 457-484  .95 .05 
 
 84-91   .62 .38 | 226-235 .79 .21 | 485-517  .96 .04    
 92-98   .63 .37 | 236-245 .80 .20 | 518-559  .97 .03 
 99-106  .64 .36 | 246-256 .81 .19 | 560-619  .98 .02
 107-113 .65 .35 | 257-267 .82 .18 | 620-735  .99 .01
 114-121 .66 .34 | 268-278 .83 .17 | over735 1.00 .00

It is easy to verify the table is actually built with standard deviation 2000/7 as an approximation for 200√2.

A citation to a detailed description of the construction of the table by Elo is desirable.

The construction by pencil and paper is not trivial and prone to errors.

Since the normal curve flattens, one would expect that the number of rating differences within one percentage row does not decrease. However, there is a discontinuity at D = 345-357, P = 89%. This suggests that the table may contain irregularities

Rtg Dif Range                
279 290 11
291 302 11  
303 315 12
316 328 12
329 344 15
345 357 12 <---
358 374 16
375 391 16  
392 411 19

KP (talk) 08:11, 4 August 2023 (UTC)[reply]

Use Outside of Chess - Other board and card games - Elo in Poker

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While not a universal metric for poker, GGPoker has incorporated an Elo rating system into one of its Sit & Go online poker formats, ‘Spin & Gold ELO’,  where player ratings are determined by win rate. Players are then awarded a letter score based on that rating, with E at the low end of 1200, A at 4000+, Master at 5000+ and Grand Master if they rank within the top 100 players. While the Elo ratings of each player affect how many points are gained or lost, they do not affect match-making.

https://www.pokerlistings.com/rise-up-the-spin-gold-elo-ranking-system-at-ggpoker

https://donkhunter.com/en/news/ggpoker-introduces-spin-gold-elo-ranking-syste,1033.html

https://www.ggpoker.com/poker-games/spin-gold-elo/ Chris H (GGPoker) (talk) 06:08, 12 October 2023 (UTC)[reply]

This page is too chess-centric

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This is a generic rating system used in many games and sports. I think a lot of this page should be moved to a new page called "Usage of the Elo rating system in Chess", or, at the very least, should be moved under a chapter with a title to that effect.

Particularly, under "Different ratings systems" (a bit of a strange title in the first place) we seem to be outlining various use cases of the system in chess and chess only.

Overall, we seem to be describing things with chess in mind, e.g. mentioning chess titles like GM, IM and organizations like FIDE, USCF etc fairly often, in places where it's not necessary.

The result is that this page would be somewhat frustrating to read for someone who wants to learn about the Elo rating system but who does not know chess. 85.146.96.60 (talk) 09:52, 20 August 2024 (UTC)[reply]

The Elo system was specifically designed for chess, so it is appropriate to discuss it in terms of the various implementations by different chess bodies. I know various on line games have a version of the Elo system but I'm not aware of any other major international sporting bodies adopting it. Besides you don't need to play chess to understand the mathematics of the system. MaxBrowne2 (talk) 04:58, 23 August 2024 (UTC)[reply]

"Suggested modification" section is misleading

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I believe the section Suggested modification, proposing 480 as a better rating difference divisor, is misleading. Any number should leave the underlying mathematics the same, resulting just in rescaled ratings. It is my understanding that the issue in the referenced article by Jeff Sonas arises only in the presence of the 400 points maximum difference cutoff, as is presented in the article. This cutoff is not integral to the Elo rating, it is not discussed elsewhere in the Wiki article and without it the whole system should just converge to slightly less spread values on its own.

If I am correct, the whole paragraph can be removed without loss. If I am wrong, perhaps it can be enhanced to prevent future readers from following my line of reasoning. — Preceding unsigned comment added by 217.28.83.193 (talk) 17:28, 6 September 2024 (UTC)[reply]

Since that section was added, I have been wondering what happened to Sonas's ideas since his article was published, in 2011. If FIDE responded to his logic by either taking his suggestion, or by making some other change, then we should acknowledge that, citing some appropriate source. Otherwise, the whole discussion is something like WP:OR from our point of view, and doesn't belong in an encyclopedia. I don't know where to look to find out about changes to FIDE's rating calculations over the years. Bruce leverett (talk) 18:37, 6 September 2024 (UTC)[reply]