Question

Question 10 A study was performed to determine whether men and women differ in their repeatability in assembling components on printed circuit boards. Random samples of 25 men and 21 women were selected, and each subject assembled the units. The two sample standard deviations of assembly time were Smen = 0.97 minutes and Swomen = 1.01 minutes. (a) Is there sufficient evidence to support the claim that men and women differ in repeatability for this assembly task at the 0.02 level of significance? (b) Find a 98% confidence interval on the ratio of the two variances. Round your answers to three decimal places (e.g. 98.765).

Answer 1

The statistical software output for this problem is:

Two sample variance summary confidence interval: G : Variance of population 1 09: Variance of population 2 Go Ratio of two variances 98% confidence interval results: Ratio Num. DF Den. DF Sample Ratio L. Limit U. Limit 20 24 10412371 038029151 29772752

Hence,

a) Yes

b) 98% confidence interval:

0.380 $\small \leq \sigma_1^2/ \sigma_2^2 \leq$ 2.977