INFORMED DECISIONS - NOTE: (For Complete File, Download link at the ...

SOLUTIONS

MANUAL

STATISTICS:

INFORMED DECISIONS

USING DATA

SIXTH EDITION

Michael Sullivan, III NOTE: (For Complete File, Download link at the end of this File) 1 / 4

Copyright © 2021 Pearson Education, Inc.Chapter 1 Data Collection Section 1.1

• (a) III. Statistics is the science of collecting,

organizing, summarizing, and analyzing information in order to draw conclusions and answer questions. It is also about providing a measure of confidence in any conclusions.(b) VIII. The population is the entire group of individuals to be studied.(c) IV. The sample is a subset of the group of individuals that is being studied.(d) VII. The parameter is a numerical summary of a population.(e) I. The statistic is the numerical summary of a sample.(f) VI. The individual is a person or object that is a member of the group being studied.(g) II. Descriptive statistics involves organizing and summarizing data through tables, graphs, and numerical summaries.(h) V. Inferential statistics uses methods that take results from a sample and extends them to the population, and measures the reliability of the result.

• (a) V. A discrete variable has either a finite

number of possible values or countable number of possible values. The values of these variables typically result from counting.(b) IV. Data are information that describe characteristics of an individual.(c) VI. A continuous variable has an infinite number of possible values that are not countable. The values of these variables typically result from measurement.(d) II. A qualitative variable allows for classification of individuals based on some attribute or characteristic.(e) I. A quantitative variable provides numerical measures of individuals. The measures can be added or subtracted, and provide meaningful results.(f) III. A variable is the characteristics of the individuals within the population.

• 18% is a parameter because it describes a

population (all of the governors).

• 72% is a parameter because it describes a

population (the entire class).

• 32% is a statistic because it describes a sample

(the high school students surveyed).

• 13.3% is a statistic because it describes a

sample (the 12th graders surveyed).

• 0.366 is a parameter because it describes a

population (all of Ty Cobb’s at-bats).

• 43.92 hours is a parameter because it describes

a population (all the men who have walked on the moon).

• 23% is a statistic because it describes a sample

(the 6076 adults studied).

• 44% is a statistic because it describes a sample

(the 100 adults interviewed).

• Qualitative 12. Quantitative
• Quantitative 14. Qualitative
• Quantitative 16. Quantitative
• Qualitative 18. Qualitative
• Discrete 20. Continuous
• Continuous 22. Discrete
• Continuous 24. Continuous
• Discrete 26. Continuous
• Nominal 28. Ordinal
• Ratio 30. Interval
• Ordinal 32. Nominal
• Ratio 34. Interval
• The population consists of all teenagers 13 to

17 years old who live in the United States.The sample consists of the 1028 teenagers 13 to 17 years old who were contacted by the Gallup Organization. 2 / 4

2 Chapter 1: Data Collection

Copyright © 2021 Pearson Education, Inc.

• The population consists of all bottles of Coca-

Cola filled by that particular machine on October 15. The sample consists of the 50 bottles of Coca-Cola that were selected by the quality control manager.

• The population consists of all of the soybean

plants in this farmer’s crop. The sample consists of the 100 soybean plants that were selected by the farmer.

• The population consists of all households

within the United States. The sample consists of the 50,000 households that are surveyed by the U.S. Census Bureau.

• The population consists of all women 27 to

44 years of age with hypertension. The sample consists of the 7373 women 27 to 44 years of age with hypertension who were included in the study.

• The population consists of all full-time

students enrolled at this large community college. The sample consists of the 128 full- time students who were surveyed by the administration.

41. Individuals: Alabama, Colorado, Indiana,

North Carolina, Wisconsin.

Variables: Minimum age for driver’s license

(unrestricted); mandatory belt use seating positions, maximum allowable speed limit (rural interstate) in 2011.

Data for minimum age for driver’s license: 17,

17, 18, 16, 18;

Data for mandatory belt use seating positions:

front, front, all, all, all; Data for maximum allowable speed limit

(rural interstate) 2011: 70, 75, 70, 70, 65

(mph.) The variable minimum age for driver’s license is continuous; the variable mandatory belt use seating positions is qualitative; the variable maximum allowable speed limit (rural interstate) 2011 is continuous (although only discrete values are typically chosen for speed limits.)

42. Individuals: 3 Series, 5 Series, 6 Series,

• Series, X3, Z4 Roadster

Variables: Body Style, Weight (lb), Number

of Seats

Data for body style: Coupe, Sedan,

Convertible, Sedan, Sport utility, Coupe;

Data for weight: 3362, 4056, 4277, 4564,

4012, 3505 (lb);

Data for number of seats: 4, 5, 4, 5, 5, 2. The

variable body style is qualitative; the variable weight is continuous; the variable number of seats is discrete.

• (a) The research objective is to determine if

adolescents who smoke have a lower IQ than nonsmokers.(b) The population is all adolescents aged 18–21. The sample consisted of 20,211 18-year-old Israeli military recruits.

(c) Descriptive statistics: The average IQ of

the smokers was 94, and the average IQ of nonsmokers was 101.(d) The conclusion is that individuals with a lower IQ are more likely to choose to smoke.

• (a) The research objective is to determine if

the application of duct tape is as effective as cryotherapy in the treatment of common warts.(b) The population is all people with warts.The sample consisted of 51 patients with warts.

(c) Descriptive statistics: 85% of patients in

group 1 and 60% of patients in group 2 had complete resolution of their warts.(d) The conclusion is that duct tape is significantly more effective in treating warts than cryotherapy.

• (a) The research objective is to determine the

proportion of adult Americans who believe the federal government wastes 51 cents or more of every dollar.(b) The population is all adult Americans aged 18 years or older.(c) The sample is the 1017 American adults aged 18 years or older that were surveyed.

(d) Descriptive statistics: Of the 1017

individuals surveyed, 35% indicated that 51 cents or more is wasted.(e) From this study, one can infer that many Americans believe the federal government wastes much of the money collected in taxes. 3 / 4

Section 1.1: Introduction to the Practice of Statistics 3

Copyright © 2021 Pearson Education, Inc.

• (a) The research objective is to determine

what proportion of adults, aged 18 and over, believe it would be a bad idea to invest $1000 in the stock market.(b) The population is all adults aged 18 and over living in the United States.(c) The sample is the 1018 adults aged 18 and over living in the United States who completed the survey.

(d) Descriptive statistics: Of the 1016 adults

surveyed, 46% believe it would be a bad idea to invest $1000 in the stock market.(e) The conclusion is that a little fewer than half of the adults in the United States believe investing $1000 in the stock market is a bad idea.

• (a) State is a qualitative variable because it is

an individual categorization.(b) F scale is a qualitative variable because each tornado is rated according to a category.(c) Fatalities is a quantitative variable because it is a numerical measure. It is a discrete variable because it is countable.(d) Length is a quantitative variable because it is a numerical measure. It is a continuous variable because it results from measurement.

• (a) State is a variable measured at the

nominal level because values of the variable name, label, or categorize. In addition, the naming scheme does not allow for the values of the variable to be arranged in a ranked or specific order.(b) F scale is a variable measured at the ordinal level because the naming scheme allows for the values of the variable to be arranged in a ranked or specific order.(c) Fatalities is a variable measured at the ratio level because the ratio of two values makes sense and a value of zero has meaning.(d) Length is a variable measured at the ratio level because the ratio of two values makes sense and a value of zero has meaning.

• Jersey number is nominal (the numbers

generally indicate a type of position played).However, if the researcher feels that lower caliber players received higher numbers, then jersey number would be ordinal since players could be ranked by their number.

• (a) Nominal; the ticket number is categorized

as a winner or a loser.(b) Ordinal; the ticket number gives an indication as to the order of arrival of guests.(c) Ratio; the implication is that the ticket number gives an indication of the number of people attending the party.

• (a) The research question is to determine if

the season of birth affects mood later in life.(b) The sample consisted of the 400 people the researchers studied.(c) The season in which you were born (winter, spring, summer, or fall) is a qualitative variable.(d) According to the article, individuals born in the summer are characterized by rapid, frequent swings between sad and cheerful moods, while those born in the winter are less likely to be irritable.(e) The conclusion was that the season at birth plays a role in one’s temperament.

• The population is the group to be studied as

defined by the research objective. A sample is any subset of the population.

• Quantitative variables are numerical measures

such that meaningful arithmetic operations can be performed on the values of the variable.Qualitative variables describe an attribute or characteristic of the individual that allows researchers to categorize the individual.The values of a discrete random variable result from counting. The values of a continuous random variable result from a measurement.

• The four levels of measurement of a variable

are nominal, ordinal, interval, and ratio.

Examples: Nominal—brand of clothing;

Ordinal—size of a car (small, mid-size, large); Interval—temperature (in degrees Celsius); Ratio—number of students in a class (Examples will vary.)

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