Consumers enjoy the deep selection of merchandise made possible by specialty stores that sacrifice breadth for greater depth. Consider stores that carry only Levi Strauss pants. The company reports that a fully stocked Levi’s store carries 130 ready-to-wear pairs of jeans for any given waist and inseam, and the company is phasing in two more lines of pants (Personal Pair and Original Spin) that it claims will eventually quadruple that number.

Source: Fortune, “The Customized, Digitized, Have-It-

Your-Way Economy”

Suppose a random sample of 24 Levi stores is sampled 2 months after the phase-in process has been launched and inventories are taken at each of the stores in the sample for all sizes of jeans. The sample mean number of choices for any given size is 141.3, and the standard deviation is 36.2. Does this sample of stores carry a greater selection of jeans, on average, than what is expected at the 0.01 level of significance?

a. Solve using the p-value approach.

b. Solve using the classical approach.