code: public static double skewness(FlatDataCollection flatDataCollection) {
  	    int n = count(flatDataCollection);
          if(n<=1) {
              throw new IllegalArgumentException("The provided collection must have more than 1 elements.");
          }
          
          double mean = mean(flatDataCollection);
          
          double m3 = moment(flatDataCollection, 3, mean);
          double variance = variance(flatDataCollection, false);        
      
          double skewness=m3/Math.pow(variance, 3.0/2.0);
          
          return skewness;
      }
docs: Calculates Skewness. Uses a formula as suggested by http://en.wikipedia.org/wiki/Skewness
  
  @param flatDataCollection
  @return