This new page lets us continue to advance our rating system. One option that has been left out so far is the option of taking into account time in ratings.
Point 1) Here is a problem with the current ratings, presented by our marvelous php developer in an email to me:
How it calculates now:
"Rating interval" equals zero. Ratings are updated on game-by-game
basis. The only check is that RD never exceeds 350.
RD' = min(350, RD).
Example for problem: there are absolutely equal players (ratings and
RDs). They play 2 simultaneous games (common case: same map, different
sides). First player wins one game and second player wins another
one. It would be ideal if players ratings aren't changed (because
players equal), only RDs changed. But now when second game is
calculated players are not equal (because of first game) and final
ratings will be inequal.
I think this is minor problem and it should be discussed in forum.
As you can see in gdescrip.pdf FICS uses game-by-game system also (as
The question is Is it really neccessary and how long should interval
be: one week, less, more? Note that Glicko works best if there are not
more than 5-10 games in rating interval per player.
Bad news: in above example if players finish games on interval's
border, ratings will be inequal again. But this situation will be
I personally don't think this is a big deal, and a tough one to solve in the case of MAN. Glicko is based on a chess system, but chess games are finished in one sitting. MAN games can take anywhere from a few hours to a couple months, depending on the availability of the players. Because of this I don't think that we should rate games based on time.
Point 2) Another problem we have though is inactive players. One solution presented by the Glicko system is to steadily increase inactive players' RD over time, so in effect we are saying we don't know how accurate the scores are anymore. I personally think this is a great idea.
Point 3) Along with this, we can have an option to sort by "pessimistic rating", which is your rating minus your RD. That puts players that have played more and played well near the top, with those that have played less but played even better slightly lower.
Any thoughts on these items?