In an experiment to compare the tensile strengths of I = 6 different types of copper wire, J = 5 samples of each type were used. The average between group and average within group estimates were computed as MSTr = 2616.3 and MSE = 1106.2, respectively. Often hypothesis tests are conducted using what is referred to as the rejection region method. This compares the calculated F test statistic to an F value that cuts off a "rejection region". If the calculated test statistic falls within the rejection region, the null is rejected. The F value that represents the cut off for the rejection region, is the F value that cuts off the top α% of area in an F distribution with I-1 and I(J-1) degrees of freedom. In other words, if α = 0.05, the F rejection region cut off will be the 95th percentile from the appropriate F distribution.