}
public void testInteraction() {
FourthMoment m4 = new FourthMoment();
Mean m = new Mean(m4);
Variance v = new Variance(m4);
Skewness s= new Skewness(m4);
Kurtosis k = new Kurtosis(m4);
for (int i = 0; i < testArray.length; i++){
m4.increment(testArray[i]);
m.increment(testArray[i]);
v.increment(testArray[i]);
s.increment(testArray[i]);
k.increment(testArray[i]);
}