Question 1

In a positively skewed distribution,the percentage of observations that fall below the median is

Accepted Answer

A) about 50 percent. 
B) less than 50 percent. 
C) more than 50 percent. 
D) cannot tell without knowing n. 
A) about 50 percent. 
B) less than 50 percent. 
C) more than 50 percent. 
D) cannot tell without knowing n. A

Question 2

Which statement is true?

Accepted Answer

A) With nominal data,we can find the mode. 
B) Outliers distort the mean,but not the standard deviation. 
C) Business and economic data are rarely skewed to the right. 
D) If we sample a normal population,the sample skewness coefficient is exactly 0. 
A) With nominal data,we can find the mode. 
B) Outliers distort the mean,but not the standard deviation. 
C) Business and economic data are rarely skewed to the right. 
D) If we sample a normal population,the sample skewness coefficient is exactly 0. A

Question 3

Referring to this box plot of ice cream fat content,the skewness would be negative.

Accepted Answer

A) True 
 B)False  True

Question 4

VenalCo Market Research surveyed 50 individuals who recently purchased a certain CD,revealing the age distribution shown below.Which statement is least defensible?

Accepted Answer

A) The mean age probably exceeds the median age. 
B) The mode would be a reasonable measure of center. 
C) The data are somewhat skewed to the left. 
D) The CD is unlikely to appeal to retirees. 
A) The mean age probably exceeds the median age. 
B) The mode would be a reasonable measure of center. 
C) The data are somewhat skewed to the left. 
D) The CD is unlikely to appeal to retirees.

Question 5

In a left-skewed distribution,we expect that the median will be greater than the mean.

Accepted Answer

A) True 
 B)False

Question 6

Find the coefficient of variation of these numbers: 14,17,17,19,26.Would the variability of those numbers be greater than,less than,or the same as the variability of 24,27,27,29,36? Defend your answer.

Accepted Answer

First sample: mean = 18.6,standard devia

Question 7

Which distribution is least likely to be skewed to the right by high values?

Accepted Answer

A) Annual incomes of n passengers on a flight from New York to London 
B) Weekend gambling losses of n customers at a major casino 
C) Accident damage losses by n renters of an auto rental company 
D) Cost of a plain McDonald's hamburger in n U.S.cities 
A) Annual incomes of n passengers on a flight from New York to London 
B) Weekend gambling losses of n customers at a major casino 
C) Accident damage losses by n renters of an auto rental company 
D) Cost of a plain McDonald's hamburger in n U.S.cities

Question 8

In Osaka,Japan,stock brokers earn ¥6000 per hour on the average,with a standard deviation of ¥1200.In Stuttgart,Germany,stock brokers earn an average of €18 per hour with a standard deviation of €6.In which country is the variation in wages greatest?

Accepted Answer

Osaka CV = 20 percent,Stuttgart CV = 33.

Question 9

The Empirical Rule assumes that the distribution of data follows a normal curve.

Accepted Answer

A) True 
 B)False

Question 10

Shown the spending by a sample of 50 breakfast customers of McDonald's.Which statement is least likely to be correct?

Accepted Answer

A) The median is very close to the midhinge. 
B) The median purchase is slightly less than $5. 
C) About 75 percent of the customers spend less than $7. 
D) The mean is a reasonable measure of center. 
A) The median is very close to the midhinge. 
B) The median purchase is slightly less than $5. 
C) About 75 percent of the customers spend less than $7. 
D) The mean is a reasonable measure of center.

Question 11

In the following data set {7,5,0,2,7,15,5,2,7,18,7,3,0},the value 7 is

Accepted Answer

A) the mean. 
B) the mode. 
C) both the mode and median. 
D) both the mean and mode. 
A) the mean. 
B) the mode. 
C) both the mode and median. 
D) both the mean and mode.

Question 12

Which is a correct statement concerning the median?

Accepted Answer

A) In a left-skewed distribution,we expect that the median will exceed the mean. 
B) The sum of the deviations around the median is zero. 
C) The median is an observed data value in any data set. 
D) The median is halfway between Q1 and Q3 on a box plot. 
A) In a left-skewed distribution,we expect that the median will exceed the mean. 
B) The sum of the deviations around the median is zero. 
C) The median is an observed data value in any data set. 
D) The median is halfway between Q1 and Q3 on a box plot.

Question 13

Three randomly chosen California students were asked how many times they drove to Mexico last year.Their replies were 4,5,6.The geometric mean is

Accepted Answer

A) 3.87 
B) 5.00 
C) 5.42 
D) 4.93 
A) 3.87 
B) 5.00 
C) 5.42 
D) 4.93

Question 14

Which is a characteristic of the standard deviation?

Accepted Answer

A) It is not greatly affected by outliers. 
B) It is measured in the same units as the mean. 
C) It measures dispersion around the median. 
D) It has a natural,concrete meaning. 
A) It is not greatly affected by outliers. 
B) It is measured in the same units as the mean. 
C) It measures dispersion around the median. 
D) It has a natural,concrete meaning.

Question 15

Kurtosis cannot be judged accurately by looking at a histogram.

Accepted Answer

A) True 
 B)False

Question 16

A survey of salary increases received during a recent year by 44 working MBA students is shown.Find the approximate mean percent raise.

Accepted Answer

A) 6.56 
B) 6.74 
C) 5.90 
D) 6.39 
A) 6.56 
B) 6.74 
C) 5.90 
D) 6.39

Question 17

Outliers are data values that fall beyond ±2 standard deviations from the mean.

Accepted Answer

A) True 
 B)False

Question 18

In calculating the sample variance,the sum of the squared deviations around the mean is divided by n − 1 to avoid underestimating the unknown population variance.

Accepted Answer

A) True 
 B)False

Question 19

Given a sample of three items (X = 4,6,5),which statement is incorrect?

Accepted Answer

A) The geometric mean is 5.2. 
B) The standard deviation is 1. 
C) The coefficient of variation is 20 percent. 
D) The quartiles are useless. 
A) The geometric mean is 5.2. 
B) The standard deviation is 1. 
C) The coefficient of variation is 20 percent. 
D) The quartiles are useless.

Question 20

The midhinge is a robust measure of center when there are outliers.

Accepted Answer

A) True 
 B)False

In a positively skewed distribution,the percentage of observations that fall below the median is

Which statement is true?

Referring to this box plot of ice cream fat content,the skewness would be negative.

VenalCo Market Research surveyed 50 individuals who recently purchased a certain CD,revealing the age distribution shown below.Which statement is least defensible?

In a left-skewed distribution,we expect that the median will be greater than the mean.

Find the coefficient of variation of these numbers: 14,17,17,19,26.Would the variability of those numbers be greater than,less than,or the same as the variability of 24,27,27,29,36? Defend your answer.

Which distribution is least likely to be skewed to the right by high values?

In Osaka,Japan,stock brokers earn ¥6000 per hour on the average,with a standard deviation of ¥1200.In Stuttgart,Germany,stock brokers earn an average of €18 per hour with a standard deviation of €6.In which country is the variation in wages greatest?

The Empirical Rule assumes that the distribution of data follows a normal curve.

Shown the spending by a sample of 50 breakfast customers of McDonald's.Which statement is least likely to be correct?

In the following data set {7,5,0,2,7,15,5,2,7,18,7,3,0},the value 7 is

Which is a correct statement concerning the median?

Three randomly chosen California students were asked how many times they drove to Mexico last year.Their replies were 4,5,6.The geometric mean is

Which is a characteristic of the standard deviation?

Kurtosis cannot be judged accurately by looking at a histogram.

A survey of salary increases received during a recent year by 44 working MBA students is shown.Find the approximate mean percent raise.

Outliers are data values that fall beyond ±2 standard deviations from the mean.

In calculating the sample variance,the sum of the squared deviations around the mean is divided by n − 1 to avoid underestimating the unknown population variance.

Given a sample of three items (X = 4,6,5),which statement is incorrect?

The midhinge is a robust measure of center when there are outliers.

Overview of Statistics

Data Collection

Describing Data Visually

Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions and Estimation

One-Sample Hypothesis Tests

Two-Sample Hypothesis Tests

Analysis of Variance

Simple Regression

Multiple Regression

Chi-Square Tests

Filters

Exam 4: Descriptive Statistics

In a positively skewed distribution,the percentage of observations that fall below the median is

Which statement is true?

Referring to this box plot of ice cream fat content,the skewness would be negative.

VenalCo Market Research surveyed 50 individuals who recently purchased a certain CD,revealing the age distribution shown below.Which statement is least defensible?

In a left-skewed distribution,we expect that the median will be greater than the mean.

Find the coefficient of variation of these numbers: 14,17,17,19,26.Would the variability of those numbers be greater than,less than,or the same as the variability of 24,27,27,29,36? Defend your answer.

Which distribution is least likely to be skewed to the right by high values?

In Osaka,Japan,stock brokers earn ¥6000 per hour on the average,with a standard deviation of ¥1200.In Stuttgart,Germany,stock brokers earn an average of €18 per hour with a standard deviation of €6.In which country is the variation in wages greatest?

The Empirical Rule assumes that the distribution of data follows a normal curve.

Shown the spending by a sample of 50 breakfast customers of McDonald's.Which statement is least likely to be correct?

In the following data set {7,5,0,2,7,15,5,2,7,18,7,3,0},the value 7 is

Which is a correct statement concerning the median?

Three randomly chosen California students were asked how many times they drove to Mexico last year.Their replies were 4,5,6.The geometric mean is

Which is a characteristic of the standard deviation?

Kurtosis cannot be judged accurately by looking at a histogram.

A survey of salary increases received during a recent year by 44 working MBA students is shown.Find the approximate mean percent raise.

Outliers are data values that fall beyond ±2 standard deviations from the mean.

In calculating the sample variance,the sum of the squared deviations around the mean is divided by n − 1 to avoid underestimating the unknown population variance.

Given a sample of three items (X = 4,6,5),which statement is incorrect?

The midhinge is a robust measure of center when there are outliers.

Overview of Statistics

Data Collection

Describing Data Visually

Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions and Estimation

One-Sample Hypothesis Tests

Two-Sample Hypothesis Tests

Analysis of Variance

Simple Regression

Multiple Regression

Chi-Square Tests

Filters