10.7. F-Test:Two-Sample for Variances Tool

Use the F-Test tool to analyze whether the variances of two variables are significantly different or not. The values of the first variable are specified in the ``Variable 1 Range:'' entry. Correspondingly, the values of the second variable are given in the ``Variable 2 Range:'' entry. ``Alpha:'' entry specifies the level of significance which is by default 95%.

If the output is printed into a range, it should contain at least three columns and eight rows.

The results are given in a table. The tool calculates and prints the mean, variance, count of observations and the degree of freedom for both variables. It also calculates the F-value, the one-tailed probability for the F-value, and the F Critical value for one-tailed test. The one-tailed probability for the F-value (``P(F<=f) one-tail'' row) describes the risk of making a Type I error of one-tailed test.

Note

This tools currently does not work correctly with missing observations.