Test Bank for Essential Statistics, 2nd Edition

Chapter 2 Test B 2-1 Chapter 2 Test B – Multiple Choice Section 2.1 (Visualizing Variation in Numerical Data) 1. [Objective: Determine significance of bin width in a histogram.] In the following histogram, what can you conclude about the bin width? a. The bin width is too small. We are given too much detail. b. The bin width is too large. We are given too much detail. c. The bin width is too small. We are hiding details of the distribution. d. The bin width is too large. We are hiding details of the distribution. 2. [Objective: Understand the difference between frequencies and relative frequencies in a histogram.] The two histograms below display the exact same data. How do the plots differ? a. Histogram (i) uses frequencies to simply count the number of observations at a given value. Histogram (ii) uses relative frequencies to show the proportion of observations at a given value. b. Histogram (i) uses relative frequencies to show the proportion of observations at a given value. Histogram (ii) uses frequencies to simply count the number of observations at a given value. c. Histograms (i) and (ii) are exactly the same; there are no differences between the plots. d. Histograms (i) and (ii) do not display the same data because the values listed on the y-axis do not match. Copyright © 2017 Pearson Education, Inc. 2-2 Chapter 2 Test B 3. [Objective: Understand the difference between how observations are recorded in dotplots and stemplots.] How are individual observations recorded in a dotplot versus a stemplot? a. A dotplot displays the actual values of observations. A stemplot uses bars to display intervals of observations. b. A dotplot displays the actual values of observations. A stemplot displays a dot for every observation. c. A dotplot displays a dot for every observation. A stemplot displays the actual values of observations. d. A dotplot displays a dot for every observation. A stemplot uses bars to display intervals of observations. 4. [Objective: Understand that a distribution of a sample of data can be displayed multiple ways.] Which dotplot represents the same data as the histogram shown below? Copyright © 2017 Pearson Education, Inc. Chapter 2 Test B 2-3 Section 2.2 (Summarizing Important Features of a Numerical Distribution) 5. [Objective: Know what to pay attention to in distributions of numerical data.] When examining distributions of numerical data, what three components should you look for? a. Shape, center, and spread b. Shape, symmetry, and spread c. Symmetry, skewness, and spread d. Symmetry, center, and spread 6. [Objective: Understand modality in distributions.] Which of the following would likely show a bimodal distribution in a histogram? a. The midterm exam scores for an introduction to Spanish course. b. The ages of students who attend a local high school. c. The number of hours a college student spends on homework per night. d. The price of college tuition, including both public and private schools. For questions (7) – (9), match one of the histograms below with its appropriate description. 7. [Objective: Recognize the shape of a distribution.] The distribution of test scores for a group of students who received a 15-minute study session prior to taking a test is displayed in histogram . 8. [Objective: Recognize the shape of a distribution.] The distribution of male heights is displayed in histogram . 9. [Objective: Recognize the shape of a distribution.] The distribution of the number of “friends” users of a popular social media site has is displayed in histogram . Copyright © 2017 Pearson Education, Inc. 2-4 Chapter 2 Test B 10. [Objective: Understand how to find typical values from a histogram.] The following histogram represents the movie runtimes (length of a movie in minutes) of 489 movies. What is the typical movie runtime according to this distribution? a. The typical value is about 90. b. The typical value is about 100. c. The typical value is about 120. d. The typical value is about 130. 11. [Objective: Determine differences in variability.] Order the following histograms from most to least variability. a. (i), (ii), (iii) b. (ii), (i), (iii) c. (ii), (iii), (i) d. (iii), (i), (ii) Copyright © 2017 Pearson Education, Inc. Chapter 2 Test B 2-5 12. [Objective: Interpreting typical values of bimodal distributions.] What is the typical value for the histogram shown below? a. The typical value is 70 because it is the average of 50 and 90. b. The typical value is 70 because it is the center of the distribution. c. Since the data are bimodal, a typical value cannot be found. d. Since the data are bimodal, there are two typical values – one is about 50 and the other is about 90. Section 2.3 (Visualizing Variation in Categorical Variables) 13. [Objective: Understand differences between bar charts and histograms.] What is the difference between a bar chart and a histogram? a. A bar chart represents categorical data and a histogram represents numerical data. b. A bar chart represents numerical data and a histogram represents categorical data. c. They can both be used to represent categorical data. d. They can both be used to represent numerical data. Copyright © 2017 Pearson Education, Inc. 2-6 Chapter 2 Test B 14. [Objective: Interpreting bar charts.] Which statement below is NOT supported by the following bar chart? a. In general, people always wear seat belts. b. About 2000 people wear seat belts “sometimes.” c. More females wear seat belts compared to males. d. More males wear seat belts compared to females. Section 2.4 (Summarizing Categorical Distributions) 15. [Objective: Determine the variability of categorical data from a bar chart.] The bar charts below depict the marital statuses of Americans, separated by gender. Which bar chart shows more variability in marital status? Why? a. The female bar chart shows more variability because many of the observations fall into one category (“Married”). b. The female bar chart shows more variability because there are more observations in the different categories than there are for males. c. The male bar chart shows more variability because many of the observations fall into one category (“Married”). d. The male bar chart shows more variability because there are more observations in the different categories than there are for females. Copyright © 2017 Pearson Education, Inc. Chapter 2 Test B 2-7 16. [Objective: Understand the term mode when describing categorical variables.] What does it mean to find the mode of a bar chart? a. The mode can be found by finding the bar, or category, with the most observations. b. You cannot find a mode for categorical data. Modes are only used with numerical data. c. The mode can be found by adding up the total number of observations and dividing by the number of categories. d. The mode can be found by adding up the total number of categories. Section 2.5 (Interpreting Graphs) Use the following information to answer questions (17) – (18): A large state university conducted a survey among their students and received 400 responses. The survey asked the students to provide the following information: * Age * Year in School (Freshman, Sophomore, Junior, Senior) * Major 17. [Objective: Determine appropriate graph based on variable type.] What type of graph would you use to describe the variable Major? a. A histogram because Major is a numerical variable. b. A histogram because Major is a categorical variable. c. A bar chart because Major is a numerical variable. d. A bar chart because Major is a categorical variable. 18. [Objective: Determine appropriate graph based on variable type.] What type of graph would you use to describe the variables Major and Year in School? a. A side-by-side bar chart should be used since these are two categorical variables. b. A side-by-side bar chart should be used since these are two numerical variables. c. A side-by-side histogram should be used since these are two categorical variables. d. A side-by-side histogram should be used since these are two numerical variables. Copyright © 2017 Pearson Education, Inc. 2-8 Chapter 2 Test B A word cloud was created using the first chapter of John Green’s The Fault in Our Stars. (Note that filler words such as “the,” “a/an,” and “and” were excluded from the plot.) Use the word cloud to answer questions (19) – (20). 19. [Objective: Interpreting word clouds.] According to the word cloud, which is the most common word in the first chapter of The Fault in Our Stars? Why? a. The most common word is “thing” because it appears in the middle of the cloud. b. The most common word is “augustus” because he is a main character in the story. c. The most common word is “hazel” because that is the narrator’s name. d. The most common word is “augustus” because it is the largest in size. 20. [Objective: Pitfalls of using word clouds.] What information is NOT explicitly portrayed in the word cloud? a. The words that occur most frequently in the chapter. b. The number of times each word occurs. c. The specific word that occurs most often. Copyright © 2017 Pearson Education, Inc. Chapter 2 Test B Chapter 2 Test B – Answer Key 1. D 2. B 3. C 4. D 5. A 6. D 7. C 8. B 9. A 10. B 11. B 12. D 13. A 14. D 15. B 16. A 17. D 18. A 19. D 20. B Copyright © 2017 Pearson Education, Inc. 2-9