Performance-based logistics. Refer to the Journal of Business Logistics (Vol. 36. 2015) study of the factors that lead to successful performance-based logistics projects. Exercise 2.45 (p. 71). Recall that opinions of a sample of Department of Defense (DOD) employees and suppliers were solicited during interviews. Data on years of experience for the 6 commercial suppliers interviewed and the 11 government employees interviewed are listed in the accompanying table. Assume these samples were randomly and independently selected from the populations of DOD employees and commercial suppliers. Consider the following claim: “On average, commercial suppliers of the DOD have less experience than government employees.”
- a. Give the null and alternative hypotheses for testing the claim.
- b. An XLSTAT printout giving the test results is shown at the bottom of the page. Find and interpret the p-value of the test using α = .05.
- c. What assumptions about the data are required for the inference, part b, to be valid? Check these assumptions graphically using the data in the PBL file.
XLSTAT Output for Exercise 8.15
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