Independent random samples selected from two normal populations produced the following sample means and standard deviations: LO5 Sample 1 Sample 2 n1 = 12 n2 = 17 x1 = 3.4 x2 = 5.9 s1 = 4.8 s2 = 3.4

a. Assuming equal variances, conduct the test H0: 1m1 - m22 = 0 against Ha: 1m1 - m22  0 using a = .05.

b. Find and interpret the 95% confidence interval for 1m1 - m22.

a. Consider the data for captains. Interpret the p-value for testing (at a = .05) whether the mean leadership values for captains from successful and unsuccessful teams differ.

b. Consider the data for flight attendants. Interpret the p-value for testing (at a = .05) whether the mean leadership values for flight attendants from successful and unsuccessful teams differ.

Successful Teams 1n = 602 Unsuccessful Teams 1n = 242 Mean Std. Dev. Mean Std. Dev. t-value p-value Captain .66 .10 .50 .20 3.72 .000 Flight Att. .40 .24 .39 .13 0.12 .907