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  1. 27 Jun '05 17:29
    What happens if a provisionally ranked 1200 player draws with another provisionally ranked 1200 player in a rated game?

    Will either rating change after the game?
  2. Standard member Wildfire
    Force of Nature
    27 Jun '05 19:56
    Originally posted by skims
    What happens if a provisionally ranked 1200 player draws with another provisionally ranked 1200 player in a rated game?

    Will either rating change after the game?
    I have no clue. Why don't you try it yourself.
  3. Standard member Bowmann
    Non-Subscriber
    03 Jul '05 16:17
    Now we know the answer.
  4. Standard member Wildfire
    Force of Nature
    03 Jul '05 20:26
    Originally posted by Bowmann
    Now we know the answer.
    Go play in someone else's sandbox.
  5. Standard member Bowmann
    Non-Subscriber
    03 Jul '05 22:37
    Originally posted by Wildfire
    Go play in someone else's sandbox.
    That reminds me, when's Katty due back?
  6. 04 Jul '05 08:42
    meeuw!
  7. Standard member Daemon Sin
    I'm A Mighty Pirateā„¢
    04 Jul '05 15:34
    Originally posted by Bowmann
    That reminds me, when's Katty due back?
    Why, you fed up chasing cars and p*ss*ng on trees already so you need your favourite leg to hump?
  8. 06 Jul '05 02:39
    If you have less than 5 games, no. Otherwise I have attepted the math:

    K=32

    Old Rating=1200

    Score = .5

    Win Expectancy = 1 / (10^((OpponentRating-YourRating)/200)+1)
    = 1 / (10^((1200-1200/200)+1)
    = 1 / (10^1)
    = 1 / 10
    = .1

    New Rating = Old Rating + K * (Score - Win Expectancy)
    = 1200 + 32 * (.5 - .1)
    = 1200 + 32 * .4
    = 1200 + 12.8
    = 1213

  9. Standard member XanthosNZ
    Cancerous Bus Crash
    06 Jul '05 10:36
    Originally posted by Invader
    If you have less than 5 games, no. Otherwise I have attepted the math:

    K=32

    Old Rating=1200

    Score = .5

    Win Expectancy = 1 / (10^((OpponentRating-YourRating)/200)+1)
    = 1 / (10^((1200-1200/200)+1)
    = 1 / (10^1)
    = 1 / 10
    = .1

    New Rating = Old Rating + K * (Score - Win Expectancy)
    ...[text shortened]... 0 + 32 * (.5 - .1)
    = 1200 + 32 * .4
    = 1200 + 12.8
    = 1213

    The win expectancy formula is used when you have played more than 20 games (your rating isn't provisional anymore).

    Until you complete 20 games (and you've completed more than 5) your rating is the average of all your game values.
    The game value is your opponent's rating + 400 if you win , -400 if you lose. It's equal to your opponent's rating if you draw.
    If your opponent is provisional the 400s are 200s.

    Therefore if two p1200's play each other and draw no change is made to their ratings.
  10. 06 Jul '05 11:29
    Originally posted by Invader
    If you have less than 5 games, no. Otherwise I have attepted the math:

    K=32

    Old Rating=1200

    Score = .5

    Win Expectancy = 1 / (10^((OpponentRating-YourRating)/200)+1)
    = 1 / (10^((1200-1200/200)+1)
    = 1 / (10^1)
    = 1 / 10
    = .1

    New Rating = Old Rating + K * (Score - Win Expectancy)
    ...[text shortened]... 0 + 32 * (.5 - .1)
    = 1200 + 32 * .4
    = 1200 + 12.8
    = 1213

    what's 'K'?
    is it always 32?
  11. Standard member XanthosNZ
    Cancerous Bus Crash
    06 Jul '05 11:52
    Originally posted by Florrat
    what's 'K'?
    is it always 32?
    Read the FAQ, it has a detailed breakdown for the rating calculation:

    "K is a constant (32 for 0-2099, 24 for 2100-2399, 16 for 2400 and above)"

    The numbers are your rating.