code: private static double hackyAdjuster(final double f) {
      final double tmp = Math.sqrt(1.0 - f);
      return (f <= 0.5) ? tmp : tmp + (0.01 * (f - 0.5));
    }
docs: This hackyAdjuster is tightly coupled with the width of the confidence interval normally
  specified with number of standard deviations. To simplify this interface the number of
  standard deviations has been fixed to 2.0, which corresponds to a confidence interval of
  95%.
  @param f the inclusion probability used to produce the set with size <i>a</i>.
  @return the hacky Adjuster