# StatisticsExcel_HypothesisTestForTwoVariances

Hypothesis Test for Two Variances:

• When to use it: To test if the variances of two populations are equal

## F-Test Example in Excel

Let's compare certain engine head dimensions from two different production lines. A sample of 10 items was taken from line 1 and a sample of 12 items was taken from line 2.

Line 1 Line 2
415.20 415.23
415.20 415.24
415.23 415.18
415.16 415.24
415.22 415.24
415.15 415.16
415.23 415.15
415.18 415.22
415.19 415.22
415.20 415.16
415.19
415.23

We will use Excel to perform a hypothesis test of equal variances of the two lines using α = 0.05 and assuming the samples come from normal distributions.

## Using Excel

Select Data, Data Analysis, F-test Two-sample for Variances. Enter the appropriate range inputs, and then click OK.

Excel should calculate the following:

Since 0.233 = p-value > $\alpha$ = 0.05 the equality of the two variances is not rejected.