On Sun, 2007-03-18 at 19:09 +0100, Sylvain Gelly wrote: > Hi Don, > > > I think what you are looking isn't a strong Anchor player, but > > strong players who are always available. > > In some sense you are right. In fact, I was not talking about anchor > with fixed rating, but "floating" anchor, which would be a player with > fixed strength, always connected. It is an anchor in the sense that > the rating of other players then depend less on which programs are > running. > And this is quite important as the rating of a player depends mainly > on the players which has a level close to it.
Yes, it's almost impossible to get an accurate rating if all your opponents are several hundred points stronger or weaker. That reminds me of another issue. The new CGOS will have a new pairing algorithm. Players will be selected who are close in strength and there will be less variety, but less mis-matched games. It's pretty much a waste of time to pair Mogo vs Random for instance and that won't happen on the new CGOS unless there just isn't enough players close to your strength. In fact, it will work more like a ladder system - but not quite as restrictive. The new pairing algorithm works like this: 1. A random value is added to each players rating for pairing. 2. Players to be scheduled are sorted according to this pseudo rating. 3. Pairings are matched pairwise in order, from top to bottom. The amount of randomness added to each players rating (for pairing purposes only) is determined dynamically. It will be a value that still guarantees a chance to get paired with at least 3 or 4 opponents on either side of your rank. Of course this algorithms also introduces a bias - you are more likely to get paired with a player next to you than with a player 2 or 3 ranks away. The gap may be greater for some players than others, as it is computed based on all available players at pairing time. But the bias is based on strength more than rank - if an opponent is only 1 rating point stronger, you are more likely to get paired against him than you are another opponent right next to you - but 150 ELO weaker. A minor enhancement is that colors against a specific opponent are no longer chosen randomly - they are equalized. So if you play white against Foo, the next time you will get black. Even if they get out of whack the server will work to correct this, but that should never happen unless the database is tampered with. Another feature is that if an opponent disconnects by accident (or on purpose), the game can continue by reconnecting. Of course the clock keeps running - there is no resuming of games the next day. The SGF files contain all the timing information for each move and the time each player takes for a given game will be reported on the web pages. The opponents name and rating will be reported to the client and passed on to the engine if it supports an extended GTP command to do this. (Any ideas on what to call this command?) Some of these features will require client support and may not immediately appear until I enhance the client versions. For instance the client can be made to produce SGF files so they do not need to be downloaded - the information needed is available to construct a clone of the SGF record stored on CGOS. - Don > So it is in this meaning I used the word "anchor", sorry for the > confusion if any. > > Sylvain _______________________________________________ computer-go mailing list [email protected] http://www.computer-go.org/mailman/listinfo/computer-go/
