In the book Essentials of Marketing Research, William R. Dillon, Thomas J. Madden, and Neil A. Firtle discuss the relationship between delivery time and computer-assisted ordering. A sample of 40 firms shows that 16 use computer-assisted ordering, while 24 do not. Furthermore, past data are used to categorize each firm's delivery times as below the industry average, equal to the industry average, or above the industry average. The results obtained are given in the table below. A Contingency Table Relating Delivery Time and Computer-Assisted Ordering Computer- Assisted Ordering No Yes Column total Below Industry Average 4 10 14 Delivery Time Equal to Industry Average 12 4 16 Above Industry Average 8 HO. independence. 2 10 Click here for the Excel Data File (a) Test the hypothesis that delivery time performance is independent of whether computer-assisted ordering is used. What do you conclude by setting a = .05? (b) Verify that a chi-square test is appropriate. Row Total The test is valid because the number of cells exceeds and the smallest Éij is greater than 24 16 40 , the average of the Eij is greater than