Question

When performing a hypothesis test for the ratio of two population variances, the upper critical F value is denoted FR. The lower critical F value, FL, can be found as follows: interchange the degrees of freedom, and then take the reciprocal of the resulting F value found in table A-5. FR can be denoted Fα/2 and FL can be denoted F1-α/2 . Find the critical values FL and FR for a two-tailed hypothesis test based on the following values: n1 = 10, n2 = 16, α = 0.05

Seleccione una: A. 0.2653, 3.7743 B. 0.3202, 3.1227 C. 3.1227, 3.7743 D. 0.2653, 3.1227

Answer 1

Given that,

= 0.05

/2 = 0.025

1 - (/2) = 0.975

n1 = 10

d.f.1 = n1 - 1 = 10 - 1 = 9   

(d.f.1 is degrees of freedom for numerator)

n2 = 16 = n2 - 1 = 16 - 1 = 15

(d.f.2 is degrees of freedom for denominator)

Use f table.

Fα/2 = F_0.025 at d.f.1 = 9 and d.f.2 = 15 = 3.1227

F1-α/2 = F_0.975  at d.f.1 = 9 and d.f.2 = 15 = 0.2653

Answer : D. 0.2653, 3.1227