Appendix A.39

F-Test (Two Variances)

Compare the variances of two populations using the F-test for equality of variances.

F-Test Calculator (Two Variances)

Compare variability between two populations

Warning: This test is extremely sensitive to departures from normality. Both populations must be normally distributed.

Sample 1

Sample 2

Null:
Alternative:
df₁:
19
df₂:
24

Calculations

s₁²
156.2500
s₂²
68.8900
df₁
19
df₂
24
Test Statistic

F-Distribution (df₁ = 19, df₂ = 24)

0.4082.3451F₀ = 2.27

Classical Approach

Critical Region: F < 0.4078 or F > 2.3452
F₀ = 2.2681 is NOT in rejection region

P-Value Approach

P-value = 0.0595
P-value α = 0.05

Fail to Reject H₀

At the α = 0.05 level, there is insufficient evidence to conclude that the two population variances are different.