Question 1

Which of the following best describes a bar chart for categorical variables?

Accepted Answer

Rectangles representing frequencies that do not touch each other.

Question 2

Given the frequency table below for student class levels, what is the relative frequency of Sophomores?

Level: Freshman (5), Sophomore (6), Junior (3), Senior (5)
Total students: 19

Use the formula $	ext{Relative Frequency} = \frac{	ext{Frequency}}{	ext{Total}}$.

Accepted Answer

$0.32$

Question 3

Which of the following is NOT a correct use of a pie chart?

Accepted Answer

Showing the distribution of a quantitative variable.

Question 4

When constructing a histogram, which rule is used to determine the number of bins?

Use the formula $2^k \geq n$, where $n$ is the sample size.

Accepted Answer

Find the smallest $k$ such that $2^k \geq n$.

Question 5

A histogram with a long tail to the right is described as:

Accepted Answer

Right-skewed

Question 6

Which of the following statements about histogram intervals is FALSE?

Accepted Answer

Intervals can overlap if the data is multimodal.

Question 7

If an observation is exactly equal to a class boundary in a histogram, where is it placed?

Accepted Answer

In the higher class.

Question 8

Which of the following best describes the difference between frequency and relative frequency?

Accepted Answer

Frequency is the count of observations; relative frequency is the proportion of observations.

Question 9

Which of the following is a recommended format for writing histogram class intervals?

Accepted Answer

$a$ to less than $b$

Question 10

A dataset of 40 observations is to be displayed in a histogram. Using the $2^k \geq n$ rule, what is the minimum number of bins $k$ you should use?

Accepted Answer

$k = 6$

Question 11

Which of the following is NOT a key feature to describe when analyzing a histogram?

Accepted Answer

Color

Question 12

A histogram is described as symmetric. What does this mean?

Accepted Answer

The right and left sides approximately mirror each other.

Question 13

Which of the following is a plausible reason for choosing too few bins in a histogram?

Accepted Answer

The graph will look like a 'pancake' and hide structure.

Question 14

Which of the following is a correct statement about unimodal distributions?

Accepted Answer

They have one peak.

Question 15

In a frequency histogram, what does the height of each rectangle represent?

Accepted Answer

The frequency of the interval.

Question 16

Which of the following is a key takeaway for categorical data analysis?

Accepted Answer

Know the difference between frequency and relative frequency.

Question 17

If a histogram is left-skewed, which of the following is true?

Accepted Answer

It has a long tail to the left.

Question 18

Which of the following is a correct statement about the placement of observations on class boundaries in histograms?

Accepted Answer

Observations equal to a class boundary are placed in the higher class.

Question 19

Which of the following is NOT a recommended practice when constructing histogram intervals?

Accepted Answer

Intervals should overlap to capture all data.

Question 20

Which of the following is a plausible consequence of choosing too many bins in a histogram?

Accepted Answer

The graph will look 'spiky' and show too much detail.

Graphical Displays and Tables: Describing Data Visually

Study Guide - Practice Questions