istics option based on
  frequentist or Bayesian statistics  to compute
  the confidence interval on the efficiencies. For each statistical
  option a corresponding static function esists taking as parameters
  <tt>n</tt>, the number of total events, <tt>k</tt>, the number of
  passed events and <tt>cl</tt> the desired confidence level and a
  boolean flag specyfing if the upper (or lower) interval boundary
  must be computed. Each statistics option can be set using the method
  <tt>TEfficiency::SetStatisti