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  1. 24 Aug '06 06:59
    I am not a paying member but can someone explain how one can lose rating pts. after a win ? I won my last game and lost 2 pts.,not all that bad but confusing. Walter 'the Wonderful'...(more or less) AKA wallyS
  2. Standard member XanthosNZ
    Cancerous Bus Crash
    24 Aug '06 07:01
    Read the FAQ. Perhaps it will illuminate your life.
  3. 24 Aug '06 07:15
    XanthosNZ, I did as U said 2 do & it is still confusing but I appreciate da help . Sure 'nuff it say my can lose pts. even wit a win. Who da thought!
    All my gots ta say 'bout dat is ....a sassafrassin' ! Walter 'the less than Wonderful'...(more or less) AKA Gator2
    Again,thanks beau coup !
  4. Standard member XanthosNZ
    Cancerous Bus Crash
    24 Aug '06 08:42
    Originally posted by Gator2
    XanthosNZ, I did as U said 2 do & it is still confusing but I appreciate da help . Sure 'nuff it say my can lose pts. even wit a win. Who da thought!
    All my gots ta say 'bout dat is ....a sassafrassin' ! Walter 'the less than Wonderful'...(more or less) AKA Gator2
    Again,thanks beau coup !
    Stop breathing. Those of us with brains need that oxygen.
  5. 24 Aug '06 09:19 / 1 edit
    Originally posted by XanthosNZ
    Stop breathing. Those of us with brains need that oxygen.
    Xantoz - Still arrogant and without social skills.

    Gator2 - Your rating is provisional until you've played 20 games. In your profile you can read the explanation: "Ratings may appear erratic until this time."
  6. Standard member XanthosNZ
    Cancerous Bus Crash
    24 Aug '06 09:34
    Originally posted by FabianFnas
    Xantoz - Still arrogant and without social skills.

    Gator2 - Your rating is provisional until you've played 20 games. In your profile you can read the explanation: "Ratings may appear erratic until this time."
    If you look in the FAQ you can find "I just won a game. Why has my rating gone down?" and then right below the answer to that question you can find the formula for provisional players and the exact reason that your rating can go down which I'll note you didn't provide.

    But of course actually providing the answer to the question (rather than a nothing explanation like you did) first and then ridiculing someone who can't understand a simple explanation is every arrogant. And this guy's inability to speak like a normal person don't help things.
  7. 24 Aug '06 10:07
    say i'm rated 2000 (yea i wish) and i beat up on a 1300 player in a rated game will i still gain points or is there a point where i'll lose rating points?
  8. 24 Aug '06 10:11
    Originally posted by kmac27
    say i'm rated 2000 (yea i wish) and i beat up on a 1300 player in a rated game will i still gain points or is there a point where i'll lose rating points?
    If you're not provisional, you will never lose rating points in a winning game. I think you will allways gain at least one point, but I'm not 100% sure.

    But for a provisional player (before the 20th game) you can actually win a lot of points just to lose to someone 500 pts over yurself. Happend my opponent in our game recently.
  9. 24 Aug '06 10:14
    if someone is provisional and the only people they play are 2400 and above and they win all of them will they be over 3000? i know its a pointless question but still come on now.
  10. Standard member XanthosNZ
    Cancerous Bus Crash
    24 Aug '06 10:18
    Originally posted by kmac27
    if someone is provisional and the only people they play are 2400 and above and they win all of them will they be over 3000? i know its a pointless question but still come on now.
    You would be average rating of your opponent + 400. Same as always.
    And no you won't always gain a point as a non-provisional player. The gap is about 600 before you don't get any points.
  11. Standard member wormwood
    If Theres Hell Below
    24 Aug '06 12:38 / 2 edits
    Originally posted by Sicilian Smaug
    Also maximum win or loss of points between players far apart in rating is 32 points.
    Win Expectancy = 1 / (10^((OpponentRating-YourRating)/400)+1).

    the 32 is the amount you win if you're exactly 400 pts lower, or lose to someone 400 pts lower. if you win a 600pts higher opponent, you'll get more than 32.

    but if you win a 400 pts lower rated player, it's only

    32*( 1 - (1/(10^(-400/400)+1)) = 32*(1-(1/1.1) = 2.9 points.

    and if I got it right, the (1-winexp) is always positive against lower rated but never zero, so in theory there's no limit for gaining rating against how ever weak opponents. but in practice the gain will be less than 1 point when you win against someone rated around 600 pts lower. and if there's internal rounding, there will be a limit.

    okay, for the 'fun' of it, lets calculate when the gain is exactly 1 point (for under 2100 rated, with k = 32 that is):

    32*(1 - (1/(10^(d/400)+1))) = 1

    1-(1/(10^(d/400)+1)) = 1/32

    1/(10^(d/400)+1) = -(1/32 - 1)

    10^(d/400) = -1/(1/32 - 1) - 1

    d = 400*log10(0.032258) = -596.54 points difference wins you exactly 1 point.

    or,

    10^(d/400) = -1/(0.5/32 - 1) - 1

    d = -719.73 points difference, if the gain is rounded from 0.5 to 1 point.

    or,

    10^(d/400) = -1/(1.5/32 - 1) - 1

    d = -523,28 if it's floored from 1.5 to 1 point.
  12. 24 Aug '06 12:52
    I would like the formula in Excel.
    Can you, or anyone, help me?
  13. Standard member XanthosNZ
    Cancerous Bus Crash
    24 Aug '06 12:58
    =32* (A1 - 1 / (10^((A2-A3)/400)+1))

    Where A1 = Score
    A2 = Opponent's Rating
    A3 = Your Rating

    That wasn't hard was it?
  14. 24 Aug '06 13:06
    Originally posted by XanthosNZ
    =32* (A1 - 1 / (10^((A2-A3)/400)+1))

    Where A1 = Score
    A2 = Opponent's Rating
    A3 = Your Rating

    That wasn't hard was it?
    As A1, Score you mean 1 for win, 0 for loss and 0.5 for draw?

    Let's test:

    A1 = 0
    A2 = 1500
    A3 = 1400
    gives A4 = -11,51792001

    I round it to nearest integer = -12, right?
  15. Standard member wormwood
    If Theres Hell Below
    24 Aug '06 13:36
    Originally posted by FabianFnas
    As A1, Score you mean 1 for win, 0 for loss and 0.5 for draw?

    Let's test:

    A1 = 0
    A2 = 1500
    A3 = 1400
    gives A4 = -11,51792001

    I round it to nearest integer = -12, right?
    yep. the rule of thumb is about 4 points per 100pts difference, starting from 16pts with even ratings.

    win a 100pts stronger opponent, you gain 16+4 = 20
    win a 200 stronger, gain 16+8 = 24
    lose to a 100 weaker, you lose 16+4 = 20
    lose to a 200 weaker, lose 16+8 = 24

    it's quite linear if the ratings are within a couple of hundreds of point. 25 points difference for 1 point gain/loss.