How is the rating deviation calculated? • page 1/1 • General Chess Discussion • lichess.org

In Lichess I was checking my stats and I found something called Rating Deviation.
All I want to know is what the rating deviation is and how Lichess calculates it.

In Lichess I was checking my stats and I found something called Rating Deviation. All I want to know is what the rating deviation is and how Lichess calculates it.

StingerPuzzles

#2

LiChess implements this http://www.glicko.net/glicko/glicko2.pdf with this adjustment http://www.glicko.net/glicko/glicko-boost.pdf as you can see here https://github.com/ornicar/lila/search?q=ratingdeviation

petri999

#3

In short Rating Deviation is standard deviation of the rating estimate you currently have. I.e. if rating is 1680 and RD is 80 then with about 66% probability you true rating would fall between 1600 and 1760. and with 98% probability 1520 and 1840.

To split hairs what it actually says: if someone has true rating of 1680 then measured with glicko-2 then the measurement result would fall between the afore mentioned limits BUT difference between the two is very very small

In short Rating Deviation is standard deviation of the rating estimate you currently have. I.e. if rating is 1680 and RD is 80 then with about 66% probability you true rating would fall between 1600 and 1760. and with 98% probability 1520 and 1840. To split hairs what it actually says: if someone has true rating of 1680 then measured with glicko-2 then the measurement result would fall between the afore mentioned limits BUT difference between the two is very very small