Test Bank for The Basic Practice of Statistics, 9e David

Test Bank for The Basic Practice of Statistics, 9e David Moore, William Notz, Michael Fligner (All Chapters Download link at the end of this file)

Chapter 1

• Employees at a large company are surveyed about their health insurance status. Employees are coded as “1”

if health insurance is obtained through the company’s benefit program, “2” if health insurance is obtained from another source (such as through a spouse’s employment benefit program), or “0” if the employee does not have

health insurance. This variable is:

• numerical.
• categorical.
• quantitatively categorical.
• All of the answer options are correct.

ANSWER: b

• A company has three divisions and three conference rooms for meetings. To keep track of the use of its

facilities, for each meeting the company records the name of the division holding the meeting, the conference room used, and the length of time of the meeting. Which of the variables is quantitative?

• the name of the division holding the meeting
• the conference room used
• the length of time of the meeting
• All of the answer options are correct.

ANSWER: c

• A description of different houses for sale includes the square footage of the house, whether or not the house

has a finished basement, and the monthly electric bill. Which of the variables is categorical?

• the square footage of the house
• whether or not the house has a finished basement
• the monthly electric bill
• All of the answer options are correct.

ANSWER: b

• Some of the variables from a survey conducted by the U.S. Census Bureau are the number of people living in

a household, the total household gross income, and the ages of household residents. Which of the variables is or are quantitative?

• the number of people living in a household
• the total household gross income
• the ages of household residents
• All of the answer options are correct.

ANSWER: d

• As part of a database of new births at a hospital, some of the variables recorded are the age of the mother, the 1 / 3

marital status of the mother (such as single, married, or divorced), the weight of the baby, and the sex of the baby. Which of the following statements is or are true?

• The individuals in this data set are births at the hospital.
• The age of the mother and the weight of the baby are quantitative variables.
• The sex of the baby and the marital status of the mother are categorical variables.
• All of the answer options are correct.

ANSWER: d

• The difference between a frequency histogram and a relative frequency histogram is that the relative

frequency histogram indicates:

• counts on the vertical (y) axis, whereas a frequency histogram indicates percents.
• counts on the horizontal (x) axis, whereas a frequency histogram indicates percents.
• percents of observations on the horizontal (x) axis, whereas a frequency histogram indicates counts.
• percents of observations on the vertical (y) axis, whereas a frequency histogram indicates counts.

ANSWER: d

• What is the difference between a histogram and a bar chart?
• There is no difference; they are exactly the same.
• A histogram is a more accurate representation of a bar chart.
• A bar chart displays a quantitative variable on the horizontal axis, whereas a histogram does not.
• A bar chart displays a categorical variable on the horizontal axis, whereas a histogram does not.

ANSWER: d

• A poll was conducted of more than 50,000 buyers of new cars, 90 days after the cars were purchased. The

data on problems per 100 vehicles for cars made by Toyota and by General Motors (GM) are given in the time plot below for the years 1998–2004. The solid line is for GM, and the dashed line is for Toyota. 2 / 3

In 2002, the number of problems per 100 vehicles was:

• about twice as high for GM as for Toyota.
• about twice as high for Toyota as for GM.
• about 20% higher for Toyota than for GM.
• about 20% higher for GM than for Toyota.

ANSWER: d

• A poll was conducted of more than 50,000 buyers of new cars, 90 days after the cars were purchased. The

data on problems per 100 vehicles for cars made by Toyota and General Motors (GM) are given in the time plot below for the years 1998–2004. The solid line is for GM and the dashed line is for Toyota.

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