Glossary
F-test
The F-distribution is formed by the ratio of two independent chi-square variables divided by their respective degrees of freedom. Since F is formed by chi-square, many of the chi-square properties carry over to the F distribution. The F-test is designed to test if two population variances are equal. It does this by comparing the ratio of two variances. Once measured, if the variances are equal, the ratio of the variances will be 1.