A Summary of Variance
Comparison Test Procedures

Using the equations on the previous pages we have established all the statistical data we need to conduct the hypothesis test.  One question remains:  What is our Hypothesis ?   Because we have established that s21 > s22, we have a choice between two possible hypotheses:


The latter of the two, 21 22 , naturally implies a right-tailed hypothesis test.  There are no left-tailed tests.  The former, 21 = 22  is the more common test and requires a two-tailed test.  How do we find the significance level ?

Procedure used to determine significance level

Case Example: Pain Medication and Response Time