So if you have been told your thyroid gland died or stopped working, ask your doctor to explain why. Make sure you have had the proper testing including a complete thyroid panel and thyroid antibody tests run. The antibody tests will catch 80-90% of the patients with Hashimotoâs.
The F-test is designed to test if two population variances are equal. It does this by comparing the ratio of two variances. So, if the variances are equal, the ratio of the variances will be 1. If the null hypothesis is true, then the F test-statistic given above can be simplified (dramatically). This ratio of sample variances will be test statistic used. If the null hypothesis is false, then we will reject the null hypothesis that the ratio was equal to 1 and our assumption that they were equal.
For a one-sided test, the null hypothesis is rejected when the test statistic is greater than the tabled value. This is demonstrated with the graph of an F distribution with Î½ 1 = 10 and Î½ 2 = 10. The shaded area of the graph indicates the rejection region at the Î± significance level.