Q: A pie chart is constructed to represent educational attainment. If the relative frequency for 'Bachelor’s Degree' is 0.2351, what is the degree measure of the sector for this category?

$$ 0.2351 \times 360$$^{\circ}$$ \approx 85$$^{\circ}$$ $$

Question 1

Which of the following best describes a frequency distribution?

Accepted Answer

A table that lists each category of data and the number of occurrences for each category.

Question 2

A physical therapist collects data on the body part requiring rehabilitation for 30 patients. She finds that 12 patients need back rehabilitation. What is the relative frequency for the 'Back' category?

Accepted Answer

$$ \frac{12}{30} = 0.4 $$

Question 3

Which type of graph is most appropriate for comparing the educational attainment of Americans in 1990 and 2021, given that the population sizes are different?

Accepted Answer

Side-by-side relative frequency bar graph

Question 4

What is a key difference between a histogram and a bar graph?

Accepted Answer

In a histogram, the rectangles touch each other; in a bar graph, they do not.

Question 5

Given the following class limits for a frequency distribution: 15–19, 20–24, 25–29, what is the class width?

Accepted Answer

$$ 20 - 15 = 5 $$

Question 6

A pie chart is constructed to represent educational attainment. If the relative frequency for 'Bachelor’s Degree' is 0.2351, what is the degree measure of the sector for this category?

Accepted Answer

$$ 0.2351 	imes 360$$^{\circ}$$ \approx 85$$^{\circ}$$ $$

Question 7

Which of the following is NOT a guideline for constructing good statistical graphics?

Accepted Answer

Use three-dimensional charts to make the data more visually appealing.

Question 8

A histogram of parking fines in New York City is described as 'fairly symmetric but not bell-shaped.' Which of the following best describes the shape of this distribution?

Accepted Answer

Symmetric

Question 9

What is the main advantage of a stem-and-leaf plot over a histogram?

Accepted Answer

The raw data can be retrieved from a stem-and-leaf plot.

Question 10

A cumulative frequency distribution for continuous data displays:

Accepted Answer

The total number of observations less than or equal to the upper class limit of a class.

Question 11

Which of the following is a potential problem with using a three-dimensional pie chart?

Accepted Answer

It can distort the perceived size of categories, making some appear larger than they are.

Question 12

If the largest value in a data set is 322.61, the smallest is 65, and you want 11 classes, what is the recommended class width?

Accepted Answer

$$ \frac{322.61 - 65}{11} \approx 23.42 $$, round up to 25

Question 13

Which of the following is true about the use of relative frequencies when comparing two data sets of different sizes?

Accepted Answer

Relative frequencies allow for meaningful comparison regardless of sample size.

Question 14

A time-series plot is most appropriate for which type of data?

Accepted Answer

Data measured at different points in time.

Question 15

Which of the following is a correct formula for calculating the class midpoint?

Accepted Answer

$$ 	ext{Class Midpoint} = \frac{	ext{Lower Class Limit} + 	ext{Upper Class Limit}}{2} $$

Question 16

Which of the following is a reason why a graph with a vertical axis that does not start at zero can be misleading?

Accepted Answer

It exaggerates the differences between categories.

Question 17

Which of the following best describes a distribution that is 'skewed right'?

Accepted Answer

The tail to the right of the peak is longer than the tail to the left.

Question 18

Why should you avoid using more than one design in the same graphic?

Accepted Answer

It can distract the reader and force attention to a specific part of the graph.

Question 19

Which of the following is a cumulative relative frequency for a class with 12 observations out of a total of 50, if the cumulative frequency up to the previous class was 20?

Accepted Answer

$$ \frac{20 + 12}{50} = 0.64 $$

Chapter 2: Organizing and Summarizing Data in Introductory Statistics

Guida di studio - Domande di pratica

Study guide - Flashcard