Class: OpenSkill::Statistics::Normal

Inherits:
Object
  • Object
show all
Defined in:
lib/openskill/statistics/normal.rb

Overview

Wrapper for normal distribution functions

Class Method Summary collapse

Class Method Details

.cdf(x) ⇒ Float

Normal cumulative distribution function (CDF)

Parameters:

  • the value

Returns:

  • the cumulative probability



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# File 'lib/openskill/statistics/normal.rb', line 13

def self.cdf(x)
  Distribution::Normal.cdf(x)
end

.inv_cdf(x) ⇒ Float

Normal inverse cumulative distribution function (inverse CDF)

Parameters:

  • the probability (0 to 1)

Returns:

  • the value at that probability



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# File 'lib/openskill/statistics/normal.rb', line 21

def self.inv_cdf(x)
  Distribution::Normal.p_value(x)
end

.pdf(x) ⇒ Float

Normal probability density function (PDF)

Parameters:

  • the value

Returns:

  • the probability density



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# File 'lib/openskill/statistics/normal.rb', line 29

def self.pdf(x)
  Distribution::Normal.pdf(x)
end