Question 1

Which of the following best describes a dotplot?

Accepted Answer

A graph of quantitative data in which each data value is plotted as a point above a horizontal scale, with dots representing equal values stacked.

Question 2

What is a key feature of a stemplot (stem-and-leaf plot)?

Accepted Answer

It arranges the sample data in order and retains the original data values.

Question 3

A time-series graph is most useful for which of the following purposes?

Accepted Answer

Revealing trends in quantitative data collected at different points in time.

Question 4

Which type of graph is best for comparing the frequencies of different categories in a data set?

Accepted Answer

Bar graph

Question 5

What distinguishes a Pareto chart from a regular bar graph?

Accepted Answer

Bars are arranged in descending order according to frequencies.

Question 6

Which of the following is a potential problem with using pictographs to represent data?

Accepted Answer

They can exaggerate differences by using two- or three-dimensional objects for one-dimensional data.

Question 7

Why is it misleading to use a nonzero vertical axis in a bar graph?

Accepted Answer

It exaggerates differences between groups by not starting the vertical scale at zero.

Question 8

Which principle did Edward Tufte recommend for constructing effective graphs?

Accepted Answer

Almost all of the ink in a graph should be used for the data, not for other design elements.

Question 9

Suppose you have a data set of 15 values. According to Tufte’s principles, what is the best way to present this data?

Accepted Answer

Use a table instead of a graph.

Question 10

A frequency polygon differs from a histogram in which way?

Accepted Answer

A frequency polygon uses line segments connected to points above class midpoints, while a histogram uses bars.

Question 11

Which of the following graphs would be most appropriate for displaying the causes of fatal plane crashes, where the categories are 'Pilot Error', 'Mechanical', 'Sabotage', 'Weather', and 'Other'?

Accepted Answer

Pareto chart

Question 12

If you want to compare the proportion of each cause of fatal plane crashes to the whole, which graph should you use?

Accepted Answer

Pie chart

Question 13

A relative frequency polygon is different from a frequency polygon in that:

Accepted Answer

It uses relative frequencies (proportions or percentages) for the vertical scale.

Question 14

Which of the following is a reason why pictographs can be misleading?

Accepted Answer

Doubling the sides of a square increases its area by a factor of four, not two.

Question 15

A researcher wants to show how the number of law enforcement fatalities has changed each year from 1985 to 2015. Which graph should they use?

Accepted Answer

Time-series graph

Question 16

Which of the following is NOT a feature of a stemplot?

Accepted Answer

It uses bars to represent frequencies.

Question 17

A bar graph is most appropriate for which type of data?

Accepted Answer

Categorical (qualitative) data

Question 18

Which of the following best describes the main purpose of a Pareto chart?

Accepted Answer

To draw attention to the more important categories by arranging bars in descending order.

Question 19

If a graph uses most of its ink for decorative elements rather than data, which principle is being violated?

Accepted Answer

Edward Tufte’s principle that almost all of the ink in a graph should be used for the data.

Question 20

Which of the following is a multi-step process for constructing a frequency polygon?

Accepted Answer

Calculate class midpoints, plot points above each midpoint for the frequency, and connect the points with line segments.

Exploring Data with Tables and Graphs: Introductory Statistics Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards