Question 1

The advantage that the coefficient of correlation has over the covariance is that the former has set lower and upper limits.

Accepted Answer

A) True 
 B)False

Question 2

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the ____________________ of ____________________.

Accepted Answer

coefficien

Question 3

The line drawn within the box of a box plot always represents the mean.

Accepted Answer

A) True 
 B)False

Question 4

The units for the variance are the same as the units for the original data (for example, feet, inches, etc.).

Accepted Answer

A) True 
 B)False

Question 5

Generally speaking, if two variables are unrelated (as one increases, the other shows no pattern), the covariance will be:

Accepted Answer

A)  a large positive number. 
B)  a large negative number. 
C)  a positive or negative number close to zero. 
D)  None of these choices. 
A)  a large positive number. 
B)  a large negative number. 
C)  a positive or negative number close to zero. 
D)  None of these choices.

Question 6

Longevity and Salary: A sample of eight observations of variables x (years of experience) and y (salary in $1,000s) is shown below:
  
-A. Calculate and interpret the covariance between x and y.
B. Give a possible reason that the covariance is negative.

Accepted Answer

A. The sign indicates a negative relatio

Question 7

According to the Empirical Rule, if the data form a bell shaped normal distribution, approximately ____________________ percent of the observations will be contained within 2 standard deviations around the mean.

Accepted Answer

The answer of According to the Empirical Rule, if the...

Question 8

The ____________________ is the least desirable of all the measures of central location.

Accepted Answer

The answer of The ____________________ is the least desirable of...

Question 9

When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate?

Accepted Answer

A)  Coefficient of variation and range 
B)  Mean and standard deviation 
C)  Interquartile range and median 
D)  Variance and interquartile range 
A)  Coefficient of variation and range 
B)  Mean and standard deviation 
C)  Interquartile range and median 
D)  Variance and interquartile range

Question 10

Which of the following are measures of the linear relationship between two variables?

Accepted Answer

A)  The covariance 
B)  The coefficient of correlation 
C)  The variance 
D)  Both a and b 
A)  The covariance 
B)  The coefficient of correlation 
C)  The variance 
D)  Both a and b

Question 11

Compute the coefficient of variation, and express the number in the appropriate unit.

Accepted Answer

cv = 2.664 thousand

Question 12

In a negatively skewed distribution, which of the following is the correct statement?

Accepted Answer

A)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3 
B)  The distance from the smallest observation to Q1 is larger than the distance from Q3 to the largest observation 
C)  The distance from the smallest observation to Q2 is smaller than the distance from Q2 to the largest observation 
D)  The distance from Q1 to Q3 is twice the distance from the Q1 to Q2 
A)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3 
B)  The distance from the smallest observation to Q1 is larger than the distance from Q3 to the largest observation 
C)  The distance from the smallest observation to Q2 is smaller than the distance from Q2 to the largest observation 
D)  The distance from Q1 to Q3 is twice the distance from the Q1 to Q2

Question 13

Test Scores: Suppose that an analysis of a set of test scores reveals that: QS1U1B11S1U1B0 = 45, QS1U1B12S1U1B0 = 85, QS1U1B13S1U1B0 = 105.
-Calculate the interquartile range. What does this tell you about the data?

Accepted Answer

IQR = Q₃ -Q_1</

Question 14

What percentage of the time will the number of containers of milk sold be more than 2 standard deviations from the mean?

Accepted Answer

Approximat

Question 15

The standard deviation is expressed in terms of the original units of measurement but the variance is not.

Accepted Answer

A) True 
 B)False

Question 16

The distance between the 25th percentile and the median is always the same as the distance between the median and the 75th percentile.

Accepted Answer

A) True 
 B)False

Question 17

Yearly Donations: The following data represent the yearly donations (in thousands of dollars) of a sample of 13 benefactors: 26.5, 23.5, 29.7, 24.8, 21.1, 24.3, 20.4, 22.7, 27.2, 23.7, 24.1, 24.8, and 28.2.
-Compute and interpret the 90th percentile.

Accepted Answer

Location = L₉₀ = 12

Question 18

The data set 10, 20, 30 has the same variance as the data set 100, 200, 300.

Accepted Answer

A) True 
 B)False

Question 19

Computers: The following data represent the number of computers owned by a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2.
-Is the distribution of the number of computers symmetric or skewed? Why?

Accepted Answer

The distribution is

Question 20

The standard deviation is the positive square root of the variance.

Accepted Answer

A) True 
 B)False

The advantage that the coefficient of correlation has over the covariance is that the former has set lower and upper limits.

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the of .

The line drawn within the box of a box plot always represents the mean.

The units for the variance are the same as the units for the original data (for example, feet, inches, etc.).

Generally speaking, if two variables are unrelated (as one increases, the other shows no pattern), the covariance will be:

Longevity and Salary: A sample of eight observations of variables x (years of experience) and y (salary in $1,000s) is shown below: -A. Calculate and interpret the covariance between x and y. B. Give a possible reason that the covariance is negative.

According to the Empirical Rule, if the data form a bell shaped normal distribution, approximately ____________________ percent of the observations will be contained within 2 standard deviations around the mean.

The ____________________ is the least desirable of all the measures of central location.

When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate?

Which of the following are measures of the linear relationship between two variables?

Compute the coefficient of variation, and express the number in the appropriate unit.

In a negatively skewed distribution, which of the following is the correct statement?

Test Scores: Suppose that an analysis of a set of test scores reveals that: Q₁ = 45, Q₂ = 85, Q₃ = 105. -Calculate the interquartile range. What does this tell you about the data?

What percentage of the time will the number of containers of milk sold be more than 2 standard deviations from the mean?

The standard deviation is expressed in terms of the original units of measurement but the variance is not.

The distance between the 25^th percentile and the median is always the same as the distance between the median and the 75^th percentile.

Yearly Donations: The following data represent the yearly donations (in thousands of dollars) of a sample of 13 benefactors: 26.5, 23.5, 29.7, 24.8, 21.1, 24.3, 20.4, 22.7, 27.2, 23.7, 24.1, 24.8, and 28.2. -Compute and interpret the 90th percentile.

The data set 10, 20, 30 has the same variance as the data set 100, 200, 300.

Computers: The following data represent the number of computers owned by a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2. -Is the distribution of the number of computers symmetric or skewed? Why?

The standard deviation is the positive square root of the variance.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations, Part 1

Inference About Comparing Two Populations, Part 2

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Review of Statistical Inference

Filters

Exam 3: Numerical Descriptive Techniques

The advantage that the coefficient of correlation has over the covariance is that the former has set lower and upper limits.

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the ____________________ of ____________________.

The line drawn within the box of a box plot always represents the mean.

The units for the variance are the same as the units for the original data (for example, feet, inches, etc.).

Generally speaking, if two variables are unrelated (as one increases, the other shows no pattern), the covariance will be:

Longevity and Salary: A sample of eight observations of variables x (years of experience) and y (salary in $1,000s) is shown below: -A. Calculate and interpret the covariance between x and y. B. Give a possible reason that the covariance is negative.

According to the Empirical Rule, if the data form a bell shaped normal distribution, approximately ____________________ percent of the observations will be contained within 2 standard deviations around the mean.

The ____________________ is the least desirable of all the measures of central location.

When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate?

Which of the following are measures of the linear relationship between two variables?

Compute the coefficient of variation, and express the number in the appropriate unit.

In a negatively skewed distribution, which of the following is the correct statement?

Test Scores: Suppose that an analysis of a set of test scores reveals that: Q1 = 45, Q2 = 85, Q3 = 105. -Calculate the interquartile range. What does this tell you about the data?

What percentage of the time will the number of containers of milk sold be more than 2 standard deviations from the mean?

The standard deviation is expressed in terms of the original units of measurement but the variance is not.

The distance between the 25th percentile and the median is always the same as the distance between the median and the 75th percentile.

Yearly Donations: The following data represent the yearly donations (in thousands of dollars) of a sample of 13 benefactors: 26.5, 23.5, 29.7, 24.8, 21.1, 24.3, 20.4, 22.7, 27.2, 23.7, 24.1, 24.8, and 28.2. -Compute and interpret the 90th percentile.

The data set 10, 20, 30 has the same variance as the data set 100, 200, 300.

Computers: The following data represent the number of computers owned by a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2. -Is the distribution of the number of computers symmetric or skewed? Why?

The standard deviation is the positive square root of the variance.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations, Part 1

Inference About Comparing Two Populations, Part 2

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Review of Statistical Inference

Filters

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the of .

Test Scores: Suppose that an analysis of a set of test scores reveals that: Q₁ = 45, Q₂ = 85, Q₃ = 105. -Calculate the interquartile range. What does this tell you about the data?

The distance between the 25^th percentile and the median is always the same as the distance between the median and the 75^th percentile.