Refer to the Journal of Business Logistics (Vol. 36, 2015) study of the factors that lead to successful performance-based logistics projects, Exercise 8.15. You used the data in the PBL file to test whether commercial suppliers have less experience, on average, than government employees. Due to small samples (n1 = 6 commercial suppliers and n2 = 11 government employees), the test requires the variance of experience to be the same for the two populations.

a. Set up the null and alternative hypotheses for a formal test of this assumption.

b. Find the value of the test statistic on the accompanying XLSTAT printout.

c. Locate the p-value of the test on the printout.

d. Using α = .05, give the appropriate conclusion. Does the result agree with your answer to 8.14c?

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Summary statistics: Variable Experience | Commercial Experience Government Std. deviation Observationa Minimum Maximum Mean 5.0000 30.0000 12.3333 8.8894 3.0000 30.0000 20.8182 9.3682 t-test for two independent samples / Lower-tailed test: 95% confidence interval on the difference between the means: (-Inf. -0.2951) Difference 8.4848 t (Observed value) t(Critical value) -1.8162 1.7551 DE 15 p-value (one-tailed) alpha 0.0447 0.05 Two-Sample T-Test and Cl: Content, Site Two-sample T for Content site Mean 89.55 SEDev SE Mean 3.07 25 0.61 09.03 3.34 0.67 Difference = p (1) -u (2) Estimate for difference: 954 CI for difference: T-Test of difference =0 (vs : T-Value = 0.57 Both use Pooled StDev = 3.2057 0.515 (-1.308, 2.338) P-Value = 0.573 DE = 48