class MoreMath::Sequence

def cover?(other, alpha = 0.05)

level.
arithmetic mean value is most likely to be equal for the +alpha+ error
Return true, if the Sequence instance covers the +other+, that is their 
def cover?(other, alpha = 0.05)
  t = t_welch(other)
  td = TDistribution.new(compute_welch_df(other))
  t.abs < td.inverse_probability(1 - alpha.abs / 2.0)
end