Fw: [pbmserv-dev] ratings in multiplayer games

["David J Bush" <twixt@cstone.net>]

| By the way, has there been any consideration to my
| suggestion (in two player games) to simply make any
| game in which the effect of a win would be to lower
| the winning players rating, simply unrated?  This
| would allow people to play teaching games without fear
| (though I believe this only affects provisional
| players, as it has been noted some games are a lot
| harder to complete 20 of than others).

In order for the ratings to have value, they should
represent an accurate statistical measure of the player's
performance. eliminating the effect of provisional player
wins against lower rated players, would arguably lead to
ratings inflation.

However, as has been pointed out, under the current
system, provisional players can lose rating points even
when they defeat HIGHER rated players. This is because
of a bias towards some median value, 1720 I think.
I'm not sure what the statistical justification of this
bias is. It applies only to provisional players.

There are other rating systems; Glicko for example, which
does not have a separate provisional system. I don't
think a player can lose rating points for a win with
Glicko. Please correct me, if I'm wrong!

David