35 lines
751 B
Ruby
35 lines
751 B
Ruby
module Statistics
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module Distribution
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class Bernoulli
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def self.density_function(n, p)
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return if n != 0 && n != 1 # The support of the distribution is n = {0, 1}.
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case n
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when 0 then 1.0 - p
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when 1 then p
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end
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end
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def self.cumulative_function(n, p)
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return if n != 0 && n != 1 # The support of the distribution is n = {0, 1}.
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case n
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when 0 then 1.0 - p
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when 1 then 1.0
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end
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end
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def self.variance(p)
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p * (1.0 - p)
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end
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def self.skewness(p)
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(1.0 - 2.0*p).to_f / Math.sqrt(p * (1.0 - p))
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end
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def self.kurtosis(p)
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(6.0 * (p ** 2) - (6 * p) + 1) / (p * (1.0 - p))
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end
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end
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end
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end
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