{- |
The newspaper "Sueddeutsche" asked their readers
what professions 16 persons have,
by only showing the photographies of them and three choices.
Their statistics was:
22% readers had 0 to 5 correct answers (category 0)
75% readers had 6 to 11 correct answers (category 1)
 3% readers had 12 to 16 correct answers (category 2)
Can this statistics be explained with random guessing,
or is there some information in the photographies
that the readers could utilize?
I got 6 correct answers.
-}moduleNumeric.Probability.Example.ProfessionwhereimportqualifiedNumeric.Probability.Distribution asDist-- type Probability = RationaltypeProbability =DoubletypeDist a =Dist.T Probability a correctAnswers ::Dist IntcorrectAnswers :: Dist Int
correctAnswers =forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sumforall a b. (a -> b) -> a -> b
$forall a. Int -> a -> [a]
replicateInt
16forall a b. (a -> b) -> a -> b
$forall prob a. Fractional prob => [(a, prob)] -> T prob a
Dist.fromFreqs [(Int
0,Probability
2),(Int
1,Probability
1)]categories ::Dist Intcategories :: Dist Int
categories =forall prob b a.
(Num prob, Ord b) =>
(a -> b) -> T prob a -> T prob b
Dist.map (\Int
n ->ifInt
n forall a. Ord a => a -> a -> Bool
<=Int
5thenInt
0elseifInt
n forall a. Ord a => a -> a -> Bool
<=Int
11thenInt
1elseInt
2)Dist Int
correctAnswers