SOLUTION MANUAL
1
,Solutions manuals understanding Basic Statistics
Table of contents
Chapter 1: Getting Started 1
Chapter 2: Organizing Data 3
Chapter 3: Averages and Variation 13
Chapter 4: Correlation and Regression 23
Chapter 5: Elementary Probability Theory 34
Chapter 6: The Binomial Probability Distribution And Related Topics 45
Chapter 7: Normal Curves and Sampling Distributions 59
Chapter 8: Estimation 74
Chapter 9: Hypothesis Testing 87
Chapter 10: Inferences About Differences 105
Chapter 11: Additional Topics Using Inference 123
1
,Chapter 1: Getting
Started Section 1.1
1. Individuals are people or objects included in the study, while a variable is a
characteristic of the individual that is measured or observed.
3. A parameter is a numerical measure that describes a population. A statistic is a
numerical value that describes a sample.
5. (a) These numerical assignments are at the nominal level. There is no apparent ordering in
the responses.
(b) These numerical assignments are at the ordinal level. There is an increasing
relationship from worst to best levels of service. These assignments are not at the
interval or ratio level. The distances between numerical responses are not
meaningful. The ratios are also not meaningful.
7. (a) Meal ordered at fast-food restaurants.
(b) Qualitative
(c) All U.S. adult fast-food consumers.
9. (a) Nitrogen concentration (milligrams of nitrogen per liter of water).
(b) Quantitative.
(c) The water in the entire lake.
11. (a) Ratio. (b) Interval. (c) Nominal. (d) Ordinal. (e) Ratio. (f) Ratio.
13. (a) Nominal. (b) Ratio. (c) Interval. (d) Ordinal. (e) Ratio. (f) Interval.
15. (a) Answers vary. Ideally, weigh the packs in pounds using a digital scale that
has tenths of pounds for accuracy.
(b) Some students may refuse to have their backpacks weighed.
(c) Informing students before class may cause students to remove items before class.
Section 1.2
1. In stratified samples, we select a random sample from each stratum. In cluster
sampling, we randomly select clusters to be included, and then each member of the
cluster is sampled.
3. Sampling error is the difference between the value of the population parameter and the
value of the sample statistic that stems from the random selection process. The term is
being used incorrectly here. Certainly larger boxes of cereal will cost more than
smaller boxes of cereal.
5. Simply use a random digits table or a computer package to randomly select four students from
the class.
(a) Answers vary. Perhaps they are excellent students who make an effort to get to class early.
(b) Answers vary. Perhaps they are busy students who are never on time to class.
(c) Answers vary. Perhaps students in the back row are introverted.
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, (d) Answers vary. Perhaps taller students are healthier.
7. Answers vary. 9. Answers vary.
11. (a) Yes, it is appropriate, as a number can repeat itself once it has occurred. The
outcome on the fourth roll is 2.
(b) We will most certainly not get the same sequence of outcomes. The process is random.
3
1
,Solutions manuals understanding Basic Statistics
Table of contents
Chapter 1: Getting Started 1
Chapter 2: Organizing Data 3
Chapter 3: Averages and Variation 13
Chapter 4: Correlation and Regression 23
Chapter 5: Elementary Probability Theory 34
Chapter 6: The Binomial Probability Distribution And Related Topics 45
Chapter 7: Normal Curves and Sampling Distributions 59
Chapter 8: Estimation 74
Chapter 9: Hypothesis Testing 87
Chapter 10: Inferences About Differences 105
Chapter 11: Additional Topics Using Inference 123
1
,Chapter 1: Getting
Started Section 1.1
1. Individuals are people or objects included in the study, while a variable is a
characteristic of the individual that is measured or observed.
3. A parameter is a numerical measure that describes a population. A statistic is a
numerical value that describes a sample.
5. (a) These numerical assignments are at the nominal level. There is no apparent ordering in
the responses.
(b) These numerical assignments are at the ordinal level. There is an increasing
relationship from worst to best levels of service. These assignments are not at the
interval or ratio level. The distances between numerical responses are not
meaningful. The ratios are also not meaningful.
7. (a) Meal ordered at fast-food restaurants.
(b) Qualitative
(c) All U.S. adult fast-food consumers.
9. (a) Nitrogen concentration (milligrams of nitrogen per liter of water).
(b) Quantitative.
(c) The water in the entire lake.
11. (a) Ratio. (b) Interval. (c) Nominal. (d) Ordinal. (e) Ratio. (f) Ratio.
13. (a) Nominal. (b) Ratio. (c) Interval. (d) Ordinal. (e) Ratio. (f) Interval.
15. (a) Answers vary. Ideally, weigh the packs in pounds using a digital scale that
has tenths of pounds for accuracy.
(b) Some students may refuse to have their backpacks weighed.
(c) Informing students before class may cause students to remove items before class.
Section 1.2
1. In stratified samples, we select a random sample from each stratum. In cluster
sampling, we randomly select clusters to be included, and then each member of the
cluster is sampled.
3. Sampling error is the difference between the value of the population parameter and the
value of the sample statistic that stems from the random selection process. The term is
being used incorrectly here. Certainly larger boxes of cereal will cost more than
smaller boxes of cereal.
5. Simply use a random digits table or a computer package to randomly select four students from
the class.
(a) Answers vary. Perhaps they are excellent students who make an effort to get to class early.
(b) Answers vary. Perhaps they are busy students who are never on time to class.
(c) Answers vary. Perhaps students in the back row are introverted.
2
, (d) Answers vary. Perhaps taller students are healthier.
7. Answers vary. 9. Answers vary.
11. (a) Yes, it is appropriate, as a number can repeat itself once it has occurred. The
outcome on the fourth roll is 2.
(b) We will most certainly not get the same sequence of outcomes. The process is random.
3
