平均值、方差与统计显著性

gistfile1.txt

require 'mathn'

def variance(arr)
  m = avg(arr)
  s = arr.map{|i| (i-m) ** 2 }.inject(:+).to_f
  s / arr.size
end

def avg(arr)
  arr.inject(:+).to_f / arr.size
end

# 数字越大越显著
def signifinance(arr1, arr2)
  f = avg(arr1) - avg(arr2)
  p = Math.sqrt(variance(arr1) ** 2 / arr1.size + 
                variance(arr2) ** 2 / arr2.size)
  f / p
end

看来你还是更喜欢ruby