question: @ Override public double conf ( double totalWeight , double delta ) { double inverseNormal = inverseNormal ( 1 - delta / 2 ) ; return 3.0d / ( 2.0d * Math . sqrt ( totalWeight ) ) * inverseNormal + ( totalWeight + Math . sqrt ( totalWeight ) ) / ( 4.0d * totalWeight * Math . sqrt ( totalWeight ) ) * Math . pow ( inverseNormal , 2.0d ) + Math . pow ( inverseNormal , 3.0d ) / ( 8.0d * totalWeight * Math . sqrt ( totalWeight ) ) ; }
target:  Calculate confidence intervall without a specific rule. 