EinStein Ratings Einstein forum

8 replies. Last post: 2006-04-08

Reply to this topic Return to forum

EinStein Ratings
  • Ingo Althofer at 2006-04-02

    New EinStein players on LittleGolem start

    with a neutral rating of 1500. Currently

    the best players are slightly/somewhat

    above 1700, and the bottom is about 1300+.

    This is well in accordance with EinStein

    ratings on the other online server

    http://www.inetplay.de, where

    start rating is 2000 (instead of 1500 on LG)

    and stable ratings are between 2200+ and

    about 1900.

    It is clear that in a game with a rather luck

    factor ratings cannot climb (and fall) arbitrarily.

    Ingo Althofer.

    PS: Currently, the ratings on LG are more volatile

    than on inetplay because of a larger influence factor

    for the single results.

  • Theo van der Storm at 2006-04-05

    Summarising Ingo Althöfer,

    if I get his spelling with o-umlaut right:

    No surprises in the ratings and games of (some) chance have a limited rating scale.

    I wish to replace his clarity (1) with mine (2):

    1. IMHO at the low end of the scale there is plenty of room

    to fall arbitrarily low, so your clarity is not mine.

    I don't want to consider all-knowing worst play.

    At the top end I agree:

    Surely an all-knowing entity could not beat Opmp by more than 77.7% :-)

    2. In a competition with free (i.e. player determined) pairing (e.g. InetPlay)

    the scale of EWN ratings can be stretched significantly, so that the rating

    difference does not reflect the win-chance by rating system design of two

    arbitrary players in a structural way. On LG this is only a very minor

    problem.

    It can be prevented by an automatic pairing system, which doesn't show

    the people registering for a game or tournament. For accuracy purposes

    it could block people registering with a very big rating difference to

    those already registered.

    And then there are the rating tournaments to fix the damage.

    By the way. Is anybody reading this?

    Theo

  • Greck at 2006-04-05

    “By the way. Is anybody reading this?”

    I do :)

  • Theo van der Storm at 2006-04-05

    Here is an exercise for a maths professor:

    Based on his playing strength player A has chance 60% to beat player B

    in a single point game.

    What is player A's chance to beat B in a best-of-5 (3 point) game?

    … and in the funny situation, that this chance is bigger than 60%,

    wouldn't that have an effect on the rating scale :-)?

    Actually, I'm quite sure he will be passing it on to a student.

    I'm a fan of Deep Thought in more than one meaning.

  • richyfourtytwo at 2006-04-05

    Here's the math if I'm not mistake (and have typedcorrectlyinto the calculator).

    0,65 + 5*0,64*0,4 + 10*0,63*0,42 = 0,68256

    So yes, as one would intuitively expect the chances are better than 60%. Hence best of 5 ratings should give a rating distribution with slightly greater width.

    Cheers

    richyfourtytwo

  • Theo van der Storm at 2006-04-05

    You have calculated the chance that the stronger player makes 5, 4 or 3 points out of 5 games. The game stops after 3 won games!

    I calculate the chance the stronger player makes 3 points in 3, 4 or 5 games

    Here's my math if I'm not mistaken:

    0,63 + 3*0,63*0,4 + 6*0,63*0,42 = 0,68256 (exact number)

    Of course. The same result, but fitting reality more closely :-)

    52% -> 53,7%

    54% -> 57,5%

    56% -> 61,1%

    58% -> 64,7%

    60% -> 68,3%

    65% -> 76,5%

    70% -> 83,7%

    76% -> 90,7%

    85% -> 97,3%

    Proost,

    Theo

    PS: 3 permutations to win in 4 (6 to win in 5),

    because the final win is a “given”.

  • Theo van der Storm at 2006-04-08

    Does anyone have the rating formula used?

  • Greck at 2006-04-08

    the formula was discussed in the forum, try google :)

Return to forum

Reply to this topic