224 Chapter Do Exercise 9.13 using R. You can rank the data with ranked.data = rank(percent). 9.14 In the study by Katz, et al., referred to previously, in which subjects answered questions about 9.15 passages they had not read, the question arises as to whether there is a relationship between how the students performed on this test and how they had performed on the SAT-Verbal when they applied to college. Why is this a relevant question? 9.16 The data relevant to Exercise 9.15 are the test scores and SAT-V scores for the 28 people in the group that did not read the passage. These data are Score 58 48 48 41 34 43 38 53 41 60 55 44 43 49 SAT-V 590 590 580 490 550 580 550 700 560 690 800 600 650 580 Score 47 33 47 40 46 53 40 45 39 47 50 53 46 53 SAT-V 660 590 600 540 610 580 620 600 560 560 570 630 510 620 Make a scatterplot of these data and draw by eye the best-fitting straight line through the points. 9. 17 Compute the correlation coefficient for the data in Exercise 9.16. Is this correlation signifi cant, and what does it mean to say that it is (or is not) significant? 9.18 Interpret the results from Exercises 9.12-9.15