View difference between Paste ID: Sb7CgQF2 and znKELNXR

 -- | Projected result of valuation A vs valuation B, with 1 = sure win
 -- for A, 0 = sure win for B.
 --
 -- This is the core formula of Elo.
 projected :: Float -> Float -> Float
-projected :: Double -> Double -> Double
+
  where e = 400
 
 -- | Points to grant the first player for a given result of a 1vs1
 points1vs1 :: Float -> Float -> Float -> Float
-points1vs1 :: Double -> Double -> Double -> Double
+points1vs1 a b d = d - projected a b
-points1vs1 a b d = c * (d - projected a b)
+
- where c = 4
+
 -- player finishing in j-th place.
 --
 -- It's important that "result i j = 1 - result j i" holds!
 result :: Int -> Int -> Float
 result i j
-result :: Int -> Int -> Double
+
   | otherwise = 0
 
 -- | Weight to put on a 1vs1 pairing. We assume that players finishing
 -- fast have played less long, and therefore reduce the weight on
 -- their results.
-pointsNvsN :: [Double] -> [Double]
+
-pointsNvsN rs =
+-- It's important that "weight i j = weight j i"
-  [ sum [ points1vs1 a b (result i j)
+weight :: Int -> Int -> Float
-        | (j, b) <- rps, i /= j]
+weight i j = 20 / fromIntegral (max i j)
 
 -- | Bonus for players close to seed level. Make it so players can never
 -- fall under 0 points.
 seedBonus :: Float -> Float -> Float
 seedBonus a v
   | v >= 0    = v
   | a < f     = v * a / f
   | otherwise = v
  where f = 300
 
 -- | NvsN evaluation. Assumes valuations are sorted by finishing placement.
 pointsFree :: [Float] -> [Float]
 pointsFree rs =
   [ seedBonus a $ sum [ weight i j * points1vs1 a b (result i j)
                       | (j, b) <- rps, i /= j]
   | (i, a) <- rps]
  where rps = zip [1..] rs