1.16 A researcher studies the average distance that 130 people living in U.S. urban areas walk each week.
A. What is the size of the sample?
B. Identify the population.
1.20 Referencing Exercise 1.16, how might you operationalize the average distance walked in one week as a(n):
B. scale measure?
1.26 A study of the effects of skin tone (light, medium, and dark) on the severity of facial wrinkles in middle age might be of interest to cosmetic surgeons.
A. What is the independent variable in this study?
B. What is the dependent variable in this study?
C. How many levels does the independent variable have?
1.32 The Kentucky Derby is perhaps the premier event in U.S. horse racing, and it provides many opportunities for identifying types of variables. For each of the following examples, identify the type of variable—nominal, ordinal, or scale.
A As racing fans, we would be very interested in the variable of finishing position. For example, a stunning upset took place in 2005 when Giacomo, a horse with 50-1 odds, won, followed by Closing Argument and then Afleet Alex.
B. We also might be interested in the variable of finishing time. Giacomo won in 2 minutes, 2.75seconds.
C If we were the betting type, we might examine the variable of payoffs. Giacomo was such a long shot that a $2.00 bet on him to win paid an incredibly high $102.60.
D We might be interested in the history of the Derby and the demographic variables of jockeys, such as gender or race. For example, in the first 28 runnings of the Kentucky Derby, 15 of the winning jockeys were African American.
E In the luxury boxes, high fashion reigns; we might be curious about the variable of hat wearing, observing how many women wear hats and how many do not.
2.13. Convert the following to percentages: 7 out of 39; 122 out of 300.
2.15. Throughout this book, final answers are reported to two decimal places. Report the following numbers this way: 0.0391, 198.2219, and 17.886.
2.42 For each of the following types of data described below, what visual displays of data would be most appropriate to use? Explain your answer clearly.
A. Eye color observed for 87 people
B. Minutes used on a cell phone by 240 teenagers
C. Time to complete the Boston Marathon for the nearly 22,000 runners who participate
D. Number of siblings for 64 college students