average AUC

  def unweightedAUC
    total = 0
    (0..(self.m_NumClasses - 1)).each do |index|
      auc = areaUnderROC(index)
      print "Class: #{index} AUC: #{auc}"
      total += auc
    end
    puts
    total.to_f/self.m_NumClasses
  end