Author: Robert Hyatt
Date: 15:25:39 01/14/03
Go up one level in this thread
On January 14, 2003 at 18:09:35, Miguel A. Ballicora wrote:
>On January 14, 2003 at 16:28:03, Robert Hyatt wrote:
>
>>On January 14, 2003 at 15:56:04, Miguel A. Ballicora wrote:
>>
>>>On January 14, 2003 at 14:53:39, Robert Hyatt wrote:
>>>
>>>>On January 14, 2003 at 12:35:02, Miguel A. Ballicora wrote:
>>>>
>>>>>On January 14, 2003 at 10:55:38, Andrew Williams wrote:
>>>>>
>>>>>>On January 14, 2003 at 10:43:20, Uri Blass wrote:
>>>>>>
>>>>>>>
>>>>>>>{Game 494 (MoveiXX vs. ACCIDENTE) ACCIDENTE resigns} 1-0
>>>>>>>Blitz rating adjustment: 2635 --> 2602
>>>>>>>
>>>>>>>Movei won a game and lost rating.
>>>>>>>
>>>>>>>Uri
>>>>>>
>>>>>>It seems a bit strange when moveixx has played a total of *thirteen* games to
>>>>>>declare that the rating system is "meaningless". What you have observed only
>>>>>>occurs in the first few games. I've forgotten now how many games it requires
>>>>>>before it settles down.
>>>>>
>>>>>Uri is poiting out a flaw.
>>>>>The point that happen when one is provisional does not make it less serious.
>>>>>After 20 games you could end up with a very wrong rating, suppose that you
>>>>>played all 1000 -1500 elo players and won all of them. Later, you will lots of
>>>>>points from the rating pool causing deflation. Overall, I think that introduces
>>>>>a lot of noise. However, considering all the mess regarding these ratings, this
>>>>>point is not one of the worst.
>>>>>
>>>>>Miguel
>>>>
>>>>This is _not_ a "flaw".
>>>
>>>It is not a flaw, it is a major screw up considering how uneven is the
>>>population of players in ICC.
>>
>>It isn't a flaw, nor a major screw-up. How about giving some good algorithm
>>to develop an approximate rating for a new player?
>
>There are many options to do it. For instance, you do not need to approximate.
>It is quite silly in the era of the computers to use paper and pencil
>approximations that Dr. Elo _had_ to do decades ago.
I'm waiting on a real suggestion. You play one game and beat a 1200 player.
What is your rating? You play another game and lose to a 1200 player. What
is your rating?
You _must_ start somewhere... And the only place you can start is by using
the ratings of the two players you have played, along with the results, to start
a first approximation to your rating.
>
>>BTW you do know that just because a new player's rating fluctuates wildly,
>>his opponents do _not_ get all those points added or subtracted from _their_
>>ratings?
>
>>>It is based on an approximation. Every approximation works between certain
>>>boundaries.
>>>
>>>>For the first 20 games, you use a "provisional rating formula" and you can lose
>>>>points by winning if you play a much lower-rated player. USCF does this.
>>>>_everybody_ does it as you have to get an initial rating from somewhere.
>>>
>>>USCF does that, that one of the reason why initial ratings in many cases are
>>>horrible and there were many cases of cheating because of this. For instance,
>>>kids that play only against 2000 rated people and their initial rating is 1600.
>>
>>What else would you propose? There is no solution. Criticizing the _only_
>>solution
>>makes little sense IMHO.
>
>What makes you think that this is the only solution?
>There are many rating systems around!
I'm waiting for a suggestion for the _initial rating_. All rating systems I
know
of use a TPR-type approximation to seed initial rating values.
>
>Even the simple solution proposed by Uri deserves consideration: not to take
>into account games were the average elo of A is >400 points than B.
>
>The one I could propose is you take the pool of players that you played and
>calculate what is the Elo that would give you the same amount of points that you
>obtained, doing the calculation "game by game", not by a crude average. For
>that, you need to iterate and that is the reason why most probably was never
>used at the beginning.
>
Er... that is what the TPR approximates, in fact. Which is _the_ point here.
To do it any other way distorts the statistical significance.
>Lots of things can be done.
>
>>>That is one of the reasons why when I started to play in US, my initial rating
>>>was way below the one that I should have had (personally I do not give a damn)
>>>because I played tournaments in the area against nobody. That is also the reason
>>>why Anatoly Karpov was rated (maybe still is) 2500 in USA. Ridiculous.
>>
>>You do realize that your rating reflects your results in a rating pool? Once
>>again
>>you are using a local rating to compare with ratings from other pools. It is
>>statistically invalid to do this.
>
>You are assuming, that I compared my elo somewhere else with the elo that I got
>in USCF and I was not happy. No, I compared the elo that I got with the elo of
>other people who played worse than me here in US. It took me a _long_ time until
>that was reversed and still my elo did not reach a balance. Partially, because
>it is difficult to increase you elo fast when you play opposition that is weaker
>than you.
That is what the statistics involved produces. And it is a _desired_ effect, in
fact.
Otherwise you could beat nobodys and produce a huge rating.
>Besides, if I did the comparison USCF ratings are slightly overrated compared to
>FIDE so even if I did, I was not wrong. I was really tired of listening to my
>opponents saying: Are you really 2050?
>
>Karpov 2596? Come on!!! He played the US Amateur and beat a couple of players
>with a very low rating and that was the result. Yes, 6 games, but he won all of
>them.
>http://www.64.com/uscf/ratings/12730227
>
So? You can't re-write the statistics to produce a result you want for a
special
case... I believe that USCF uses a FIDE rating as the initial rating if the
player
has one. If not, it has to do _something_.
>Miguel
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