Question 1

Which of the following best describes the five-number summary of a data set?

Accepted Answer

The minimum, first quartile, median, third quartile, and maximum

Question 2

Given a data set with $$Q_1 = 2.2$, Q_3$ = 9.4$$, and $$IQR = 7.2$$, what is the formula for the lower fence used to detect outliers?

Accepted Answer

$$Q_1 - 1.5$$ 	imes IQR$$

Question 3

A boxplot shows a right whisker much longer than the left, and the median is left of center in the box. What does this indicate about the distribution?

Accepted Answer

The distribution is skewed right

Question 4

Refer to the third image above. What do the dots to the right of the boxplot represent?

Accepted Answer

Outliers

Question 5

If a ride distance of 42.3 miles is marked as an outlier in a boxplot, which of the following is true?

Accepted Answer

It is greater than the upper fence

Question 6

In the fourth image, what does the comparison of the two boxplots suggest about the ride distances for shared and not shared rides?

Accepted Answer

Not shared rides have a higher median and more dispersion

Question 7

Which measure of central tendency is most appropriate to report for a highly skewed data set with outliers?

Accepted Answer

Median

Question 8

What is the interquartile range (IQR) and how is it calculated?

Accepted Answer

The difference between the third and first quartiles: $$IQR = Q_3$ - Q_1$

Question 9

Which of the following statements about outliers is correct?

Accepted Answer

Outliers can occur by chance, measurement error, or sampling error

Question 10

If the five-number summary of a data set is: 0.4, 2.2, 4.85, 9.4, 42.3, what is the range of the data?

Accepted Answer

$$42.3 - 0.4 = 41.9$$

Question 11

Which of the following is NOT a step in constructing a boxplot?

Accepted Answer

Calculate the mean and standard deviation

Question 12

Why is the interquartile range (IQR) considered a resistant measure of spread?

Accepted Answer

It is not affected by extreme values or outliers

Question 13

If a data value is less than the lower fence or greater than the upper fence, what is it considered?

Accepted Answer

An outlier

Question 14

Which of the following best describes the purpose of a boxplot?

Accepted Answer

To visually summarize the distribution, center, spread, and outliers of a data set

Numerically Summarizing Data: Measures of Central Tendency, Dispersion, and Position

Study Guide - Practice Questions

Study Guide - Flashcards