Author: Uri Blass
Date: 13:43:16 01/15/03
Go up one level in this thread
On January 15, 2003 at 13:00:32, Robert Hyatt wrote: >On January 15, 2003 at 12:20:14, Uri Blass wrote: > >>On January 15, 2003 at 11:51:53, Robert Hyatt wrote: >> >>>On January 15, 2003 at 11:09:32, Miguel A. Ballicora wrote: >>> >>>>On January 14, 2003 at 20:47:46, Robert Hyatt wrote: >>>> >>>>>On January 14, 2003 at 19:47:21, Uri Blass wrote: >>>> >>>>[snip] >>>> >>>>>>I do not suggest exactly how to do it and it seems that the problem does not >>>>>>interest the ICC. >>>>> >>>>> >>>>>ICC is not interested. FIDE is not interested. USCF is not interested. In >>>>>fact, _no_ chess federation I know of does the initial rating differently than >>>>>what is done today. >>>> >>>> >>>>I told you already, FIDE does not do it in the same way. >>> >>>Have they changed this recently? My last official rules from FIDE used >>>the _same_ "provisional rating" formula that everyone else uses. The >>>classic win+400 + draw + lose-400 / N formula that ICC uses. >>> >>>So I guess I don't understand what you mean, assuming they _have_ changed >>>the way that they calculate _initial_ ratings. >>> >>> >>>> >>>> >>>>>You are taking a rating as an absolute value. It is _not_. It is an >>>>>estimate of how you would do against the group (pool) of players you compete >>>>>in. The current TPR approach is _exact_ in that regard. Even if it has >>>>>nothing to do with how you would do against other players. I have _yet_ to >>>>>see anyone suggest an alternative. Just complaints about how it is done now. >>>>> >>>>>Without suggestions on a better way, complaints are not very useful... >>>>> >>>>>"I don't like that, fix it" is _not_ going to produce changes. >>>> >>>> >>>>Please read my other message. First, you posted "I am waiting a real >>>>suggestion". I did (in two messages), you ignored them. Uri mention another >>>>possibility. >>>> >>>> >>>>>>If ICC cares about creating a better rating system >>>>>>They can give give 10000$ for the people who find the best rating system. >>>>> >>>>>I believe Elo did that a _long_ time back. It has certainly stood the >>>>>"test of time". >>>> >>>>The theory yes, but the implementation is far from perfect and many people >>>>suggested improvements, including Glickman and K. Thompson. >>> >>>You realize why the glickman system was developed? The Elo system had >>>some basic assumptions, one of which was that active players might play one >>>event per month. That means their rating should change more quickly than >>>what is happening today where on a chess server, a person can play 20 games >>>in a single day. The Glickman formula slows your rating change as you play >>>more games over a short period of time. IE on ICC Crafty's rating can change >>>+/-200 in a single afternoon as a loss to a player rated 300-400 points lower >>>will cost it 32 rating points in one game. In the glicko system, that 32 points >>>would be more like 1-2 points if it had been playing lots of games every day. >>> >>>Elo wasn't wrong. But his assumptions are not always reasonable in a >>>world connected via the internet. But for _either_ rating system, the >>>initial rating is calculated the same way because no better way has been >>>found. >>> >>> >>> >>>> >>>>>>It seems that they do not care so they will not do it. >>>>>> >>>>>>I have also definition that we can compare based on it different rating systems. >>>>>>A rating system should give the expected result in every game. >>>>>>It is easy to use the sum of squares to find the practical error and the rating >>>>>>system that gives the smallest error is the most logical rating to choose. >>>>>> >>>>>>Uri >>>>> >>>>>Can you spell "Elo"??? >>>> >>>>This is rather insulting. You are dealing with Uri and me like we are two >>>>schoolboys and you are not more qualified than any of us in this matter. I do >>>>not mind it if it comes with some content, but you are not even reading the >>>>messages. Uri pointed out a problem and you come with the >>>>"'I don't like that, fix it' is _not_ going to produce changes." >>>>What? it is not possible to post anymore something about something that you do >>>>not like? Before you find a solution, you have to identify a problem and discuss >>>>about it. Not to mention, suggestions were provided. >>>> >>>>Miguel >>> >>> >>>It wasn't intended to be insulting. It was intended to point out that >>>what you are talking about is _exactly_ what the Elo system was designed to >>>do. >>> >>>Neither of you have produced any _reasonable_ approach to initially compute >>>a players rating. That seems to be all that is in debate here, as once the >>>provisional period is up, the Elo system seems to be accepted by all, even >>>with the minor "flaw" in the assumption of what K should be. But for the >>>provisional period I have seen _no_ suggestion that makes any sense yet. I >>>have asked you in another post to simply make a precise formulation of an >>>algorithm that you think is better. I can then show you why it is not better >>>the current simple TPR average that everyone I can find is using, FIDE >>>included according to a web search a few minutes ago. >> >>Here is a simple algorithm that is better and I think it was suggested by >>migual. >> >>1)If the player has only wins or only losses do not give the player rating. > >Bad idea. Strong player at a university could win every tournament game >he plays there. He gets _no_ rating??? no rating means that we do not know the rating and not that the player is weak. I agree that no information is not a good idea. I suggest that the player will get information but the information will include only lower bound for rating. lower bound can be calculated by reducing 1/2 point from the result and calculating rating. > > >>2)If the player has not only wins or only losses decide to do the following >>steps(note that this is not the fastest way but I care only to make the way >>clear and not to do it fast). >> >>a)Guess a rating that for the player based on results >>b)calculate for every game the expected result based on the rating(the elo gives >>expected result for every difference of rating) >>c)You will find that the result is too low or too high >>d)if the result is too high reduce the rating by 1/2 and repeat the process >>until you find that the rating is too low. >>e)if the rating is too low increase the rating by 1/2 and repeat the process >>until you find that the rating is too high. >>f)You will get 2 numbers with difference 1/2 and the rating is between them > > >and you will get a number that is _very_ close to the TPR number if you measure >it over 20 games. That is the point.. The number that I get cannot be reduced by winning. The order of games is not important. Note that my opinion is that this is not the best idea because I think that the order of games should be important because players may learn and improve from playing so the last games should be more important. I do not know how much more important but they should be more important. It is espacially the case when computers are involved and there may be an upgrade in the hardware or the software. Uri Uri
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.