Question 1

Which of the following best describes a frequency table?

Accepted Answer

A table that organizes categorical data by count (or frequency) or percentage (or relative frequency) from each category.

Question 2

A bar chart is most appropriate for displaying which type of data?

Accepted Answer

Categorical data, showing the count or percentage for each category.

Question 3

Suppose you have the following data set: {6, 2, 7, 4}. What is the median?

Accepted Answer

$$\frac{4 + 6}{2} = 5$$

Question 4

Which measure of center is most appropriate for a highly right-skewed distribution, such as household income?

Accepted Answer

Median

Question 5

Given the Enron price change data with a maximum of $$21.06$$ and a minimum of $$-17.75$$, what is the range?

Accepted Answer

$$21.06 - (-17.75) = 38.81$$

Question 6

Which of the following statements about the mean and median is TRUE for a left-skewed distribution?

Accepted Answer

The mean is less than the median.

Question 7

A company advertises that its new iPad has a mean lifetime of 5 years with a standard deviation of 2 years. What does the standard deviation tell you about the product?

Accepted Answer

The lifetimes of the iPads are spread out, with most being within 2 years of the mean.

Question 8

Which of the following is NOT a property of the interquartile range (IQR)?

Accepted Answer

It is highly influenced by extreme values.

Question 9

A histogram is best used to:

Accepted Answer

Display the distribution of numerical data by showing the frequency of data within equal intervals (bins).

Question 10

If a distribution is symmetric, which of the following is most likely TRUE?

Accepted Answer

The mean and median are approximately equal.

Question 11

Which of the following best explains why the U.S. Census Bureau reports the median family income instead of the mean?

Accepted Answer

The distribution of income is skewed to the right, so the median better represents the typical family.

Question 12

Which of the following is the correct formula for the sample standard deviation $$s of a $$data set $$x_1$$, $$x_2$$, ..., x_n$$ with sample mean $$\bar{x}$$?

Accepted Answer

$$s = \sqrt{\frac{\sum_{i=1}^n (x_i - \bar{x})^2$}{n-1}}$$

Question 13

A boxplot is useful for which of the following purposes?

Accepted Answer

Comparing the distribution, center, and spread of two or more groups.

Question 14

Which of the following is a key advantage of using a pie chart?

Accepted Answer

It gives a quick impression of how a whole group is partitioned into categories.

Question 15

Suppose a data set has a mean of 10 and a standard deviation of 0. What can you conclude about the data?

Accepted Answer

All values in the data set are equal to 10.

Question 16

If a histogram of hospital charges is right-skewed, which measure of center is most likely to be higher?

Accepted Answer

Mean

Question 17

Which of the following is a limitation of using the range as a measure of variability?

Accepted Answer

It is highly sensitive to extreme values (outliers).

Question 18

A company wants to compare the consistency of two products' lifespans. Which measure should they use?

Accepted Answer

Standard deviation

Question 19

Which of the following best describes a right-skewed distribution?

Accepted Answer

The right tail is longer; most values are on the left.

Question 20

If a data set has a mean of 20, a median of 15, and is highly skewed, which direction is it skewed?

Accepted Answer

Right-skewed

Data Description: Organizing and Visualizing Categorical Data in Business Statistics

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드