Question 1

A high school volleyball coach has summarized the wins, losses, and ties of her team for the past 4 years in the following stacked bar chart. Interpret the chart.

Accepted Answer

The answer of A high school volleyball coach has summarized...

Question 2

A variable is a characteristic that changes or varies over time, and/or for different individuals or objects under consideration. An experimental unit is the individual or object on which a variable is measured.

Accepted Answer

This statement is true. Variables can change over time and across different units or individuals, and experimental units are the entities on which variables are measured in an experiment.

Question 3

A histogram is usually used to display which of the following characteristics for a quantitative variable?
A) the shape of the distribution
B) the spread or variability in the data
C) the approximate center of the data
D) the spread or variability in the data and the approximate center of the data
E) all of these

Accepted Answer

A histogram shows the shape of the distribution, the spread or variability in the data, and the approximate center of the data. It is a useful tool for summarizing and visualizing quantitative data.

Question 4

Statistical inference is the process of making an estimate, prediction, or decision about a population based on sample data.

Accepted Answer

This statement accurately defines statistical inference.

Question 5

A neighborhood ice cream vendor would like to see if there is a relationship between day of the week and the number of children buying ice cream from her. The following data represent the number of children buying ice cream on each of the seven days of a particular week:  
a. Construct a line chart to describe the data.
b. Is there any apparent trend in the data?
________________________________________________________

Accepted Answer

The answer of A neighborhood ice cream vendor would like...

Question 6

The following data represents the number of pages of notes per lecture taken by a student in a beginning statistics course.
1 5 2 6 2 3 3 4 4 4 5
5 5 5 5 5 6 6 6 6 6 6
6 6 5 6 4 5 6
a. Construct a dotplot to describe the data.
b. Would you describe the distribution of the data as symmetric, skewed to the right or skewed to the left?
______________
c. Explain.
________________________________________________________

Accepted Answer

The answer of The following data represents the number of...

Question 7

The owner of an Italian restaurant would like to see a graphical display of the number of customers that the restaurant serves. The following data are the average number of customers served each day for the last 12 months.
  Construct a line graph.
Explain what the graph tells us.
________________________________________________________

Accepted Answer

The answer of The owner of an Italian restaurant would...

Question 8

The stem-and-leaf plot is used to display the distribution of:
A) qualitative data
B) quantitative data
C) two quantitative variables on the same chart
D) all of these

Accepted Answer

A stem-and-leaf plot is a graphical display of quantitative data where the “stem” represents the first digit or digits and the “leaves” represent the remaining digits. This type of plot is commonly used to display distribution of univariate quantitative data. Therefore, choice B is the correct answer.

Question 9

A bar chart is used to display a:
A) time series data
B) continuous variable
C) qualitative variable
D) quantitative variable
E) discrete variable

Accepted Answer

Bar charts are typically used to display qualitative or categorical data, where each bar represents a category.

Question 10

A limnologist is studying a Minnesota lake in October. He records the temperatures in °C for surface water taken every other day at noon. The data are shown below.
8.5 8.1 7.9 9.0 7.7 7.3 7.1 6.8 9.2
6.8 6.3 7.0 6.5 5.7 5.9 4.9 4.2 6.9
a. Construct a stem and leaf plot to display the distribution of the data.
  
b. Would you describe the distribution of the data as symmetric, skewed to the right or skewed to the left?
______________
c. Explain.
________________________________________________________

Accepted Answer

The answer of A limnologist is studying a Minnesota lake...

Question 11

If the manager of a grocery store wishes to display the sales trend, the most effective type of graph will be:
A) a bar chart
B) a pie chart
C) a histogram
D) a line chart
E) all of these

Accepted Answer

A line chart would be the most effective type of graph to display sales trends over time since it can show changes over time and highlight any patterns or trends in the data. A bar chart would be useful to compare sales between different categories or products, but it would not show the trend over time very clearly. A pie chart and a histogram are not appropriate for displaying sales trends.

Question 12

One of the differences between a histogram and bar chart is:
A) that the bar chart does have gaps between the bars and the histogram does not
B) that the histogram is used to display the distribution of quantitative data and the bar chart is used to display qualitative data
C) that the width of the bars is the same in both the histogram and the bar chart
D) all of these
E) none of these

Accepted Answer

The answer of One of the differences between a histogram...

Question 13

Bar and pie charts are graphical techniques for qualitative data. The former focus the attention on the frequency of the occurrences of the categories, and the later emphasize the percentage of occurrences of each category.

Accepted Answer

Bar charts are used to display the frequency of different categories of qualitative data, showing each category as a separate bar, while pie charts represent the same type of data by showing the proportion of each category as a slice of a pie, emphasizing the percentage or proportion of each category within the whole.

Question 14

Twenty-five percent of a sample of 200 professional tennis players indicated that their parents did not play tennis. This is an example of descriptive statistics as opposed to inferential statistics.

Accepted Answer

This statement describes a characteristic or feature of the sample, and does not involve making generalizations or predictions beyond the sample itself. Therefore, it is an example of descriptive statistics.

Question 15

A local cable system using a sample of 1000 subscribers estimates that fifty percent of its subscribers watch premium channel at least five times per week. This is an example of inferential statistics as opposed to descriptive statistics.

Accepted Answer

This is an example of inferential statistics because the sample of 1000 subscribers is being used to make an inference about the proportion of all subscribers who watch premium channels at least five times per week. Descriptive statistics would simply describe the characteristics of the sample itself, without making any inference to the larger population.

Question 16

Individual observations within each class may be found in a frequency distribution.

Accepted Answer

A frequency distribution summarizes the data by reporting the number of observations within each class or category, but it does not list individual observations.

Question 17

Which of the following statements is false?
A) A bar chart and histogram can be used interchangeably.
B) The bars on a bar chart have the same width.
C) The simplest graph for quantitative data is the dotplot.
D) There are gaps between the bars in a bar chart.
E) All of these.

Accepted Answer

A bar chart and histogram cannot be used interchangeably as they have different purposes and display different types of data. A bar chart is used to display categorical data while a histogram is used to display numerical data.

Question 18

In a sample of 1000 students in a university, 125 of them or 12.5% are biology majors. The 12.5% is an example of statistical inference.

Accepted Answer

The statement is not an example of statistical inference, but rather a descriptive statistic of the sample. Statistical inference involves making predictions or generalizations about a larger population based on data from a sample.

Question 19

The librarian of a small community library has compiled the number of people who visited the library and the respective number of checked-out books, and created the line chart shown below:  Interpret the chart, where the solid line is the number of visitors and the dashed line is the number of books checked-out.
________________________________________________________

Accepted Answer

The answer of The librarian of a small community library...

Question 20

A math teacher would like to present the midterm results to her class in a way that shows the overall spread of the data. The 25 test scores for the midterm are listed below.
a. Construct a dotplot.
45 78 62 98 50 61 91 89 57 64 77 69 82 73 70 73 79 80 68 72 62 65 78 50 95
b. Explain what the plot tells us.
________________________________________________________

Accepted Answer

The answer of A math teacher would like to present...

Quiz 1: Describing Data With Graphs

A high school volleyball coach has summarized the wins, losses, and ties of her team for the past 4 years in the following stacked bar chart. Interpret the chart.

A variable is a characteristic that changes or varies over time, and/or for different individuals or objects under consideration. An experimental unit is the individual or object on which a variable is measured.

A histogram is usually used to display which of the following characteristics for a quantitative variable?

Statistical inference is the process of making an estimate, prediction, or decision about a population based on sample data.

The stem-and-leaf plot is used to display the distribution of:

A bar chart is used to display a:

If the manager of a grocery store wishes to display the sales trend, the most effective type of graph will be:

One of the differences between a histogram and bar chart is:

Bar and pie charts are graphical techniques for qualitative data. The former focus the attention on the frequency of the occurrences of the categories, and the later emphasize the percentage of occurrences of each category.

Twenty-five percent of a sample of 200 professional tennis players indicated that their parents did not play tennis. This is an example of descriptive statistics as opposed to inferential statistics.

A local cable system using a sample of 1000 subscribers estimates that fifty percent of its subscribers watch premium channel at least five times per week. This is an example of inferential statistics as opposed to descriptive statistics.

Individual observations within each class may be found in a frequency distribution.

Which of the following statements is false?

In a sample of 1000 students in a university, 125 of them or 12.5% are biology majors. The 12.5% is an example of statistical inference.