38. Adding computerized medical images to a database promises to provide great resources for physicians. However, there are other methods of obtaining such information, so the issue of efficiency of access needs to be investigated. The article "The Comparative Effectiveness of Conventional and Digital Image Libraries". of Audiovisual Media in Medicine, 2001: 8-15) reported on an experiment in which 13 computer- proficient medical professionals were timed both while retrieving an image from a library of slides and while retrieving the same image from a computer database with a Web front end. Subject 1 2 E 3 4 Slide 30 35 40 25 Digital 25 16 15 15 Difference 5 19 25 Subject 8 9 10 Slide 62 40 51 Digital 16 15 13 11 Difference 46 25 38 +9 == 5 6 7 20 30 35 10 20 7 10 10 28 12 13 25 42 33 19 19 14 23 14 a. Construct a comparative boxplot of times for the two types of retrieval, and comment on any interesting features. b. Estimate the difference between true average times for the two types of retrieval in a way that conveys infor- mation about precision and reliability. Be sure to check the plausibility of any assumptions needed in your analysis. Does it appear plausible that the true average times for the two types of retrieval are identical? Why or why not? 40. Refer to Exercise 38. What is for the test when true average DNA content is identical for three of the diets and falls below this common value by 1 standard devia-