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How did the Glicko2 System work in the following case?

#1

Hi all,
just would like to understand it:
These were 2 of my last games that I lost:

5+3 • Blitz • Rated
37 minutes ago
NewbieMcNewface
1400 −6
Aryan_445511
1417 +6

5+3 • Blitz • Rated
48 minutes ago
Aryan_445511
1411 +6
NewbieMcNewface
1405 −5

In the first one, I lost 5 points and in the 2nd one 6. How can this be? Why isn't it the same or less in the 2nd game (since my opponent was a little stronger rated and I a little weaker than in the first game?
Is there some floating point thing going on in the background?

Sorry, not sure if this belongs in Lichess feedback after all, since I assume the algorithm works as it should.

Hi all, just would like to understand it: These were 2 of my last games that I lost: 5+3 • Blitz • Rated 37 minutes ago NewbieMcNewface 1400 −6 Aryan_445511 1417 +6 5+3 • Blitz • Rated 48 minutes ago Aryan_445511 1411 +6 NewbieMcNewface 1405 −5 In the first one, I lost 5 points and in the 2nd one 6. How can this be? Why isn't it the same or less in the 2nd game (since my opponent was a little stronger rated and I a little weaker than in the first game? Is there some floating point thing going on in the background? Sorry, not sure if this belongs in Lichess feedback after all, since I assume the algorithm works as it should.
#3

What were the rating deviations?

What were the rating deviations?
#4

@yit6
Sorry, are you asking me? Can I look that up somewhere? Not even sure what "rating deviations" is. Does this mean the bigger the change the longer one hasen't played?
I thought of that, too. But these two games were right one after another (rematch)

Edit: figured it out: it says: Rating deviation: 45.01.

@yit6 Sorry, are you asking me? Can I look that up somewhere? Not even sure what "rating deviations" is. Does this mean the bigger the change the longer one hasen't played? I thought of that, too. But these two games were right one after another (rematch) Edit: figured it out: it says: Rating deviation: 45.01.
#5

I think that if your opponent is weaker, and you lose, you will lose more points. On the other hand, if your opponent is stronger, you will lose less points.

I think that if your opponent is weaker, and you lose, you will lose more points. On the other hand, if your opponent is stronger, you will lose less points.
#6

https://en.wikipedia.org/wiki/Glicko_rating_system
The rating deviation is how stable your rating is. Higher rating deviation means your rating changes more.
Having a higher rating deviation means your rating changes more, according to the formulas

https://en.wikipedia.org/wiki/Glicko_rating_system The rating deviation is how stable your rating is. Higher rating deviation means your rating changes more. Having a higher rating deviation means your rating changes more, according to the formulas
#7

@yit6
Thanks, I figured that out now:
My rating deviation was: 45.01.

But imho this still doesen't explain why this happened.

@yit6 Thanks, I figured that out now: My rating deviation was: 45.01. But imho this still doesen't explain why this happened.
#8

Here are the calculations for the Glicko-2 system: http://www.glicko.net/glicko/glicko2.pdf

A possible answer for this is that your opponent's rating deviation decreased after the first game. Usually your RD decreases after a game, regardless of result. Since your opponent's RD decreased after the first game, their rating became more stable, and lichess determined that it was more accurate than before. If you opponent's RD is lower, then your own rating will change by a larger amount after a game result. In principle, this makes sense: if your opponent's RD is high, it means that their rating is unstable/inaccurate, meaning that lichess won't change your rating as much after the game. However, if your opponent's RD is low, it means their rating is stable and accurate, so lichess is more confident when it calculates your new rating.

A final detail is that rating deviation actually has a larger impact on rating change than the difference between you and your opponent's ratings.

Here are the calculations for the Glicko-2 system: http://www.glicko.net/glicko/glicko2.pdf A possible answer for this is that your opponent's rating deviation decreased after the first game. Usually your RD decreases after a game, regardless of result. Since your opponent's RD decreased after the first game, their rating became more stable, and lichess determined that it was more accurate than before. If you opponent's RD is lower, then your own rating will change by a larger amount after a game result. In principle, this makes sense: if your opponent's RD is high, it means that their rating is unstable/inaccurate, meaning that lichess won't change your rating as much after the game. However, if your opponent's RD is low, it means their rating is stable and accurate, so lichess is more confident when it calculates your new rating. A final detail is that rating deviation actually has a larger impact on rating change than the difference between you and your opponent's ratings.
#9

Also these changes are rounded values: if the rating increases from 1500.95 (displayed as 1500) to 1506.05 (displayed as 1506), then the actual change is +5.1, while the displayed change is +6.

Also these changes are rounded values: if the rating increases from 1500.95 (displayed as 1500) to 1506.05 (displayed as 1506), then the actual change is +5.1, while the displayed change is +6.
#10

Thank you very much for your answers, BACollin and NM oberschlumpf!
I think that explains it!

Thank you very much for your answers, BACollin and NM oberschlumpf! I think that explains it!

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