Test Bank for Elementary Statistics 13th Edition by Mario F. Triola
CONTENTS
Chapter 1: Introduction To Statistics
Section 1-1: Statistical and Critical Thinking ................................................................... 1
Section 1-2: Types of Data ................................................................................................ 3
Section 1-3: Collecting Sample Data ................................................................................ 3
Chapter Quick Quiz........................................................................................................... 5
Review Exercises ..............................................................................................................5
Cumulative Review Exercises ........................................................................................... 6
Chapter 2: Exploring Data with Tables and Graphs
Section 2-1: Frequency Distributions for Organizing and Summarizing Data ................. 7
Section 2-2: Histograms .................................................................................................. 12
Section 2-3: Graphs That Enlighten and Graphs That Deceive ...................................... 14
Section 2-4: Scatterplots, Correlation, and Regression ................................................... 17
Chapter Quick Quiz......................................................................................................... 18
Review Exercises ............................................................................................................19
Cumulative Review Exercises ......................................................................................... 20
Chapter 3: Describing, Exploring, and Comparing Data
Section 3-1: Measures of Center .....................................................................................21
Section 3-2: Measures of Variation .................................................................................26
Section 3-3: Measures of Relative Standing and Boxplots ............................................. 31
Chapter Quick Quiz......................................................................................................... 34
Review Exercises ............................................................................................................35
Cumulative Review Exercises ......................................................................................... 36
Chapter 4: Probability
Section 4-1: Basic Concepts of Probability ..................................................................... 37
Section 4-2: Addition Rule and Multiplication Rule ...................................................... 39
Section 4-3: Complements, Conditional Probability, and Bayes’ Theorem ................... 41
Section 4-4: Counting .....................................................................................................43
Chapter Quick Quiz......................................................................................................... 45
Review Exercises ............................................................................................................46
Cumulative Review Exercises ......................................................................................... 47
Chapter 5: Discrete Probability Distributions
Section 5-1: Probability Distributions .............................................................................49
Section 5-2: Binomial Probability Distributions. ............................................................ 51
Section 5-3: Poisson Probability Distributions ............................................................... 54
Chapter Quick Quiz......................................................................................................... 55
Review Exercises ............................................................................................................56
Cumulative Review Exercises ......................................................................................... 57
,Chapter 6: Normal Probability Distributions
Section 6-1: The Standard Normal Distribution..............................................................59
Section 6-2: Real Applications of Normal Distributions ................................................60
Section 6-3: Sampling Distributions and Estimators.......................................................64
Section 6-4: The Central Limit Theorem ........................................................................68
Section 6-5: Assessing Normality ...................................................................................71
Section 6-6: Normal as Approximation to Binomial ......................................................75
Chapter Quick Quiz.........................................................................................................77
Review Exercises ........................................................................................................... 78
Cumulative Review Exercises ........................................................................................ 79
Chapter 7: Estimating Parameters and Determining Sample Sizes
Section 7-1: Estimating a Population Proportion. .......................................................... 81
Section 7-2: Estimating a Population Mean. .................................................................. 85
Section 7-3: Estimating a Population Standard Deviation or Variance ..........................89
Section 7-4: Bootstrapping: Using Technology for Estimates ........................................92
Chapter Quick Quiz.........................................................................................................94
Review Exercises ........................................................................................................... 95
Cumulative Review Exercises ........................................................................................ 96
Chapter 8: Hypothesis Testing
Section 8-1: Basics of Hypothesis Testing ......................................................................97
Section 8-2: Testing a Claim About a Proportion ...........................................................99
Section 8-3: Testing a Claim About a Mean .................................................................105
Section 8-4: Testing a Claim About a Standard Deviation or Variance ...................... 109
Chapter Quick Quiz.......................................................................................................112
Review Exercises ......................................................................................................... 112
Cumulative Review Exercises ...................................................................................... 113
Chapter 9: Chapter 9: Inferences from Two Samples
Section 9-1: Two Proportions....................................................................................... 115
Section 9-2: Two Means: Independent Samples ...........................................................124
Section 9-3: Two Dependent Samples (Matched Pairs)............................................... 130
Section 9-4: Two Variances or Standard Deviations ....................................................134
Chapter Quick Quiz.......................................................................................................136
Review Exercises ......................................................................................................... 137
Cumulative Review Exercises ...................................................................................... 138
Chapter 10: Correlation and Regression
Section 10-1: Correlation ..............................................................................................141
Section 10-2: Regression ...............................................................................................148
Section 10-3: Prediction Intervals and Variation ..........................................................157
Section 10-4: Multiple Regression. ...............................................................................159
Section 10-5: Nonlinear Regression ..............................................................................161
Chapter Quick Quiz.......................................................................................................165
Review Exercises ......................................................................................................... 165
Cumulative Review Exercises ...................................................................................... 166
,Chapter 11: Goodness-of-Fit and Contingency Tables
Section 11-1: Goodness-of-Fit ......................................................................................169
Section 11-2: Contingency Tables ................................................................................173
Chapter Quick Quiz.......................................................................................................177
Review Exercises ......................................................................................................... 178
Cumulative Review Exercises ...................................................................................... 179
Chapter 12: Analysis of Variance
Section 12-1: One-Way ANOVA .................................................................................181
Section 12-2: Two-Way ANOVA .................................................................................183
Chapter Quick Quiz.......................................................................................................184
Review Exercises ......................................................................................................... 185
Cumulative Review Exercises ...................................................................................... 186
Chapter 13: Nonparametric Tests
Section 13-2: Sign Test .................................................................................................189
Section 13-3: Wilcoxon Signed-Ranks Test for Matched Pairs ....................................190
Section 13-4: Wilcoxon Rank-Sum Test for Two Independent samples ......................192
Section 13-5: Kruskal-Wallis Test for Three or More Samples ....................................195
Section 13-6: Rank Correlation .....................................................................................196
Section 13-7: Runs Test for Randomness .................................................................... 198
Chapter Quick Quiz.......................................................................................................199
Review Exercises ......................................................................................................... 200
Cumulative Review Exercises ...................................................................................... 201
Chapter 14: Statistical Process Control
Section 14-1: Control Charts for Variation and Mean ..................................................203
Section 14-2: Control Charts for Attributes ..................................................................205
Chapter Quick Quiz.......................................................................................................210
Review Exercises ......................................................................................................... 210
Cumulative Review Exercises ...................................................................................... 212
, Chapter 1: Introduction to Statistics 1
Chapter 1: Introduction to Statistics
Section 1-1: Statistical and Critical Thinking
1. The respondents are a voluntary response sample or a self-selected sample. Because those with strong
interests in the topic are more likely to respond, it is very possible that their responses do not reflect the
opinions or behavior of the general population.
2. a. The sample consists of the 1046 adults who were surveyed. The population consists of all adults.
b. When asked, respondents might be inclined to avoid the shame of the unhealthy habit of not washing
their hands, so the reported rate of 70% might well be much higher than it is in reality. It is generally
better to observe or measure human behavior than to ask subjects about it.
3. Statistical significance is indicated when methods of statistics are used to reach a conclusion that a
treatment is effective, but common sense might suggest that the treatment does not make enough of a
difference to justify its use or to be practical. Yes, it is possible for a study to have statistical significance,
but not practical significance.
4. No. Correlation does not imply causation. The example illustrates a correlation that is clearly not the result
of any interaction or cause effect relationship between deaths in swimming pools and power generated from
nuclear power plants.
5. Yes, there does appear to be a potential to create a bias.
6. No, there does not appear to be a potential to create a bias.
7. No, there does not appear to be a potential to create a bias.
8. Yes, there does appear to be a potential to create a bias.
9. The sample is a voluntary response sample and has strong potential to be flawed.
10. The samples are voluntary response samples and have potential for being flawed, but this approach might
be necessary due to ethical considerations involved in randomly selecting subjects and somehow imposing
treatments on them.
11. The sampling method appears to be sound.
12. The sampling method appears to be sound.
13. With only a 1% chance of getting such results with a program that has no effect, the program appears to
have statistical significance. Also, because the average loss of 22 pounds does seem substantial, the
program appears to also have practical significance.
14. Because there is a 0.3% chance of getting such results by chance, the increase in scores does appear to have
statistical significance. The typical increase of 5 points suggests that the course does have practical
significance. The course does appear to be successful.
15. Because there is a 19% chance of getting that many girls by chance, the method appears to lack statistical
significance. The result of 1020 girls in 2000 births (51% girls) is above the approximately 50% rate
expected by chance, but it does not appear to be high enough to have practical significance. Not many
couples would bother with a procedure that raises the likelihood of a girl from 50% to 51%.
16. Because there is a 25% chance of getting such results with a program that has no effect, the program does
not appear to have statistical significance. Because the average increase is only 3 IQ points, the program
does not appear to have practical significance.
17. Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same subject, so each pair is
matched.
18. No. The source is from university researchers who do not appear to gain from distorting the data.
19. The data can be used to address the issue of whether there is a correlation between body temperatures at
8 AM and at 12 AM. Also, the data can be used to determine whether there are differences between body
temperatures at 8 AM and at 12 AM.
20. Because the differences could easily occur by chance (with a 64% chance), the differences do not appear to
have statistical significance.
21. No. The white blood cell counts measure a different quantity than the red blood cell counts, so their
differences are meaningless.
Copyright © 2018 Pearson Education, Inc.
CONTENTS
Chapter 1: Introduction To Statistics
Section 1-1: Statistical and Critical Thinking ................................................................... 1
Section 1-2: Types of Data ................................................................................................ 3
Section 1-3: Collecting Sample Data ................................................................................ 3
Chapter Quick Quiz........................................................................................................... 5
Review Exercises ..............................................................................................................5
Cumulative Review Exercises ........................................................................................... 6
Chapter 2: Exploring Data with Tables and Graphs
Section 2-1: Frequency Distributions for Organizing and Summarizing Data ................. 7
Section 2-2: Histograms .................................................................................................. 12
Section 2-3: Graphs That Enlighten and Graphs That Deceive ...................................... 14
Section 2-4: Scatterplots, Correlation, and Regression ................................................... 17
Chapter Quick Quiz......................................................................................................... 18
Review Exercises ............................................................................................................19
Cumulative Review Exercises ......................................................................................... 20
Chapter 3: Describing, Exploring, and Comparing Data
Section 3-1: Measures of Center .....................................................................................21
Section 3-2: Measures of Variation .................................................................................26
Section 3-3: Measures of Relative Standing and Boxplots ............................................. 31
Chapter Quick Quiz......................................................................................................... 34
Review Exercises ............................................................................................................35
Cumulative Review Exercises ......................................................................................... 36
Chapter 4: Probability
Section 4-1: Basic Concepts of Probability ..................................................................... 37
Section 4-2: Addition Rule and Multiplication Rule ...................................................... 39
Section 4-3: Complements, Conditional Probability, and Bayes’ Theorem ................... 41
Section 4-4: Counting .....................................................................................................43
Chapter Quick Quiz......................................................................................................... 45
Review Exercises ............................................................................................................46
Cumulative Review Exercises ......................................................................................... 47
Chapter 5: Discrete Probability Distributions
Section 5-1: Probability Distributions .............................................................................49
Section 5-2: Binomial Probability Distributions. ............................................................ 51
Section 5-3: Poisson Probability Distributions ............................................................... 54
Chapter Quick Quiz......................................................................................................... 55
Review Exercises ............................................................................................................56
Cumulative Review Exercises ......................................................................................... 57
,Chapter 6: Normal Probability Distributions
Section 6-1: The Standard Normal Distribution..............................................................59
Section 6-2: Real Applications of Normal Distributions ................................................60
Section 6-3: Sampling Distributions and Estimators.......................................................64
Section 6-4: The Central Limit Theorem ........................................................................68
Section 6-5: Assessing Normality ...................................................................................71
Section 6-6: Normal as Approximation to Binomial ......................................................75
Chapter Quick Quiz.........................................................................................................77
Review Exercises ........................................................................................................... 78
Cumulative Review Exercises ........................................................................................ 79
Chapter 7: Estimating Parameters and Determining Sample Sizes
Section 7-1: Estimating a Population Proportion. .......................................................... 81
Section 7-2: Estimating a Population Mean. .................................................................. 85
Section 7-3: Estimating a Population Standard Deviation or Variance ..........................89
Section 7-4: Bootstrapping: Using Technology for Estimates ........................................92
Chapter Quick Quiz.........................................................................................................94
Review Exercises ........................................................................................................... 95
Cumulative Review Exercises ........................................................................................ 96
Chapter 8: Hypothesis Testing
Section 8-1: Basics of Hypothesis Testing ......................................................................97
Section 8-2: Testing a Claim About a Proportion ...........................................................99
Section 8-3: Testing a Claim About a Mean .................................................................105
Section 8-4: Testing a Claim About a Standard Deviation or Variance ...................... 109
Chapter Quick Quiz.......................................................................................................112
Review Exercises ......................................................................................................... 112
Cumulative Review Exercises ...................................................................................... 113
Chapter 9: Chapter 9: Inferences from Two Samples
Section 9-1: Two Proportions....................................................................................... 115
Section 9-2: Two Means: Independent Samples ...........................................................124
Section 9-3: Two Dependent Samples (Matched Pairs)............................................... 130
Section 9-4: Two Variances or Standard Deviations ....................................................134
Chapter Quick Quiz.......................................................................................................136
Review Exercises ......................................................................................................... 137
Cumulative Review Exercises ...................................................................................... 138
Chapter 10: Correlation and Regression
Section 10-1: Correlation ..............................................................................................141
Section 10-2: Regression ...............................................................................................148
Section 10-3: Prediction Intervals and Variation ..........................................................157
Section 10-4: Multiple Regression. ...............................................................................159
Section 10-5: Nonlinear Regression ..............................................................................161
Chapter Quick Quiz.......................................................................................................165
Review Exercises ......................................................................................................... 165
Cumulative Review Exercises ...................................................................................... 166
,Chapter 11: Goodness-of-Fit and Contingency Tables
Section 11-1: Goodness-of-Fit ......................................................................................169
Section 11-2: Contingency Tables ................................................................................173
Chapter Quick Quiz.......................................................................................................177
Review Exercises ......................................................................................................... 178
Cumulative Review Exercises ...................................................................................... 179
Chapter 12: Analysis of Variance
Section 12-1: One-Way ANOVA .................................................................................181
Section 12-2: Two-Way ANOVA .................................................................................183
Chapter Quick Quiz.......................................................................................................184
Review Exercises ......................................................................................................... 185
Cumulative Review Exercises ...................................................................................... 186
Chapter 13: Nonparametric Tests
Section 13-2: Sign Test .................................................................................................189
Section 13-3: Wilcoxon Signed-Ranks Test for Matched Pairs ....................................190
Section 13-4: Wilcoxon Rank-Sum Test for Two Independent samples ......................192
Section 13-5: Kruskal-Wallis Test for Three or More Samples ....................................195
Section 13-6: Rank Correlation .....................................................................................196
Section 13-7: Runs Test for Randomness .................................................................... 198
Chapter Quick Quiz.......................................................................................................199
Review Exercises ......................................................................................................... 200
Cumulative Review Exercises ...................................................................................... 201
Chapter 14: Statistical Process Control
Section 14-1: Control Charts for Variation and Mean ..................................................203
Section 14-2: Control Charts for Attributes ..................................................................205
Chapter Quick Quiz.......................................................................................................210
Review Exercises ......................................................................................................... 210
Cumulative Review Exercises ...................................................................................... 212
, Chapter 1: Introduction to Statistics 1
Chapter 1: Introduction to Statistics
Section 1-1: Statistical and Critical Thinking
1. The respondents are a voluntary response sample or a self-selected sample. Because those with strong
interests in the topic are more likely to respond, it is very possible that their responses do not reflect the
opinions or behavior of the general population.
2. a. The sample consists of the 1046 adults who were surveyed. The population consists of all adults.
b. When asked, respondents might be inclined to avoid the shame of the unhealthy habit of not washing
their hands, so the reported rate of 70% might well be much higher than it is in reality. It is generally
better to observe or measure human behavior than to ask subjects about it.
3. Statistical significance is indicated when methods of statistics are used to reach a conclusion that a
treatment is effective, but common sense might suggest that the treatment does not make enough of a
difference to justify its use or to be practical. Yes, it is possible for a study to have statistical significance,
but not practical significance.
4. No. Correlation does not imply causation. The example illustrates a correlation that is clearly not the result
of any interaction or cause effect relationship between deaths in swimming pools and power generated from
nuclear power plants.
5. Yes, there does appear to be a potential to create a bias.
6. No, there does not appear to be a potential to create a bias.
7. No, there does not appear to be a potential to create a bias.
8. Yes, there does appear to be a potential to create a bias.
9. The sample is a voluntary response sample and has strong potential to be flawed.
10. The samples are voluntary response samples and have potential for being flawed, but this approach might
be necessary due to ethical considerations involved in randomly selecting subjects and somehow imposing
treatments on them.
11. The sampling method appears to be sound.
12. The sampling method appears to be sound.
13. With only a 1% chance of getting such results with a program that has no effect, the program appears to
have statistical significance. Also, because the average loss of 22 pounds does seem substantial, the
program appears to also have practical significance.
14. Because there is a 0.3% chance of getting such results by chance, the increase in scores does appear to have
statistical significance. The typical increase of 5 points suggests that the course does have practical
significance. The course does appear to be successful.
15. Because there is a 19% chance of getting that many girls by chance, the method appears to lack statistical
significance. The result of 1020 girls in 2000 births (51% girls) is above the approximately 50% rate
expected by chance, but it does not appear to be high enough to have practical significance. Not many
couples would bother with a procedure that raises the likelihood of a girl from 50% to 51%.
16. Because there is a 25% chance of getting such results with a program that has no effect, the program does
not appear to have statistical significance. Because the average increase is only 3 IQ points, the program
does not appear to have practical significance.
17. Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same subject, so each pair is
matched.
18. No. The source is from university researchers who do not appear to gain from distorting the data.
19. The data can be used to address the issue of whether there is a correlation between body temperatures at
8 AM and at 12 AM. Also, the data can be used to determine whether there are differences between body
temperatures at 8 AM and at 12 AM.
20. Because the differences could easily occur by chance (with a 64% chance), the differences do not appear to
have statistical significance.
21. No. The white blood cell counts measure a different quantity than the red blood cell counts, so their
differences are meaningless.
Copyright © 2018 Pearson Education, Inc.
