ELO calculations

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Laporbo
Posts: 1
Joined: 10 July 2020, 10:00

ELO calculations

Post by Laporbo »

Trying to figure out this ELO thing. How is it calculated?

Why is it that if I win I get +3 to +6 or if I'm lucky +10 BUT if I lose I lose -15 or -23 or more?? Seems a bit lopsided.
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korrigan421
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Joined: 21 April 2014, 20:31

Re: ELO calculations

Post by korrigan421 »

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ArtfulSoul
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Joined: 16 July 2020, 18:03

Re: ELO calculations

Post by ArtfulSoul »

I don't really understand it either. If I play 2-player, my rank 180, opponent rank 300, and I lose by 1 point (with only 25% chance I could win), I lose 7 ELO points? Gosh, seems like I did pretty well at "almost" winning, but ELO points are far higher.
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Jest Phulin
Posts: 1856
Joined: 08 July 2013, 21:50

Re: ELO calculations

Post by Jest Phulin »

ELO is not an arbitrary reward for a win or a penalty for a loss. It is a pool of points shared by all players. Winners gain points by taking them from the losers. Theoretically the sum of all ELO of all players is a constant. On this site, though, it gets increased with each new player of a game -- new players cannot lose ELO.

Now, I know people will say "but my opponent lost 30 ELO, and I only gained 15." This is due to the k-factors being different, which allows for ELO to represent actual skill at a game more quickly. Once all players are established, this difference goes away.

As far as losing by only one point? If a boxing title is on the line, does it matter if it is a first-round knock-out, or a 10th round split decision by the judges? The title can only go to one person. The loser doesn't get to claim part of the title no matter how well they did versus the odds-makers.
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Romain672
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Joined: 05 April 2016, 13:53

Re: ELO calculations

Post by Romain672 »

ELO calculation doesn't take in consideration how close you was to win.

Per example, if you finish second on a 4 player game:
- you will lost elo from the player who goes first
- you will won elo from the player who goes third
- you will won elo from the player who goes forth

This gain will increase if you have less elo than the other person.
This loss will be more big if you have more elo than the other person.

[At that, you have a multiplicator depending of the number of players (more there is players, more this multiplcator is high).]=> edit: not sure about that.
And you got a second one (K-factor) which depend of the number of games you played. Once you played 20 games, this K-factor stay at 20.

.

It ask so much work to make the system gave or remove elo depending of how close you was to win.
Some game are atrocious for knowing which player should be second.
Some game finish at 30/27 and aren't close at all.
Some game ('snowbally') can easily be close while 70% of the game, and finish not close at all.
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Meeplelowda
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Joined: 14 March 2020, 10:31

Re: ELO calculations

Post by Meeplelowda »

Romain672 wrote: 16 July 2020, 18:52 It ask so much work to make the system gave or remove elo depending of how close you was to win.
Too much work, and kind of silly. Close only counts in horseshoes and hand grenades. :D

ELO was originally designed for chess ratings. Win, lose, or draw are the only scoring outcomes. Although in principle I can see factoring in how much material each player had at the end as a kind of "score," but that's not part of the system. On further reflection, however, that's also silly. For example, if you lose to a Fool's Mate you have the same amount of material on the board but the loss is NOT EVEN CLOSE.
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eagle53
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Joined: 21 July 2020, 18:53

Re: ELO calculations

Post by eagle53 »

Where is your ELO score shown or where can it be found? I am a new player.
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Jest Phulin
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Joined: 08 July 2013, 21:50

Re: ELO calculations

Post by Jest Phulin »

eagle53 wrote: 21 July 2020, 18:56 Where is your ELO score shown or where can it be found? I am a new player.
It is the number next to the laurel wreath, normally in a bluish-greyish box. (The box changes color depending on how high the number is.)

It can be found next to the player name when at a table (either waiting, actively playing, or at the end-game summary), or in the XP section of a player's profile. At the end-game summary, it will also list in integer values the total adjustment to one's ELO. Hovering over this will display detailed calculations to the hundredth's decimal place.

ELO scores are intentionally not shown at a table in Arena Mode during play, however.
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