Losing your first game deducts too many points

[RolandSC2]

I noticed some bloke lose 64 points on his first game against a similarly rated player. The victor went from 1204 to 1219, and the loser went from 1200 to 1136. Seems like losing that many points could be discouraging at that point in the player's experience (his/her first game).

 

 

Edited August 21, 2018 by RolandSC2

[Tiber7]

I

Edited March 3, 2022 by Tiber7

[Guest]

# Lower ratings "move faster" and change more
# dramatically than higher ones. Anything rating above
# this value moves at the same rate as this value.
elo_k_factor_constant_rating = 2200.0

# This preset number of games is the number of games
# where a player is considered "stable".
# Rating volatility is constant after this number.
volatility_constant = 20.0

Copy-pasted snippet from 0.A.D's ELO implementation. I suppose thats just how ELO works.

[coworotel]

https://en.wikipedia.org/wiki/Elo_rating_system

[Tiber7]

T

Edited March 3, 2022 by Tiber7

[sarcoma]

I think scythe's implementation departs too far from true ELO

https://blog.mackie.io/the-elo-algorithm

Rn = Ro + K * (S - E)

n=400

x = Ra - Rb
s = n/ln(10)
exponent = -(x/s)
E = 1/(1+e^exponent)

K = (2*n)/20

vs

  player_volatility = (min(games_played, volatility_constant) / volatility_constant + 0.25) / 1.25
  rating_k_factor = 50.0 * (min(rating, elo_k_factor_constant_rating) / elo_k_factor_constant_rating + 1.0) / 2.0
  volatility = rating_k_factor * player_volatility
  difference = opponent_rating - rating

return round(max(0, (difference + result * elo_sure_win_difference) / volatility - anti_inflation))

 

And maybe other systems would be more appropriate, like Glicko or the ones that work for teams too.

[Guest]

For an RTS game, I am not sure whether true ELO could be even used.

58 minutes ago, sarcoma said:

And maybe other systems would be more appropriate, like Glicko or the ones that work for teams too.

Curren implementation can handle team game ratings. Its just not used. Understandable considering how broken even 1v1 ratings are.

Regarding Glicko, @mapkoc has a thread detailing his implementation of it.

IMO, current ELO is pretty much good enough. Whats really needed is to make sure that all 1v1 rated games change players ratings.

[sarcoma]

This free online/proprietary system promises wonders and is based in glicko just like trueskill