Question 1

The symbol for the population coefficient of correlation is:

Accepted Answer

A)  r 
B)  $\rho$ 
C)  r2 
D)  $\rho$2 
A)  r 
B)  $\rho$ 
C)  r2 
D)  $\rho$2 B

Question 2

Game Winnings & Education: An ardent fan of television game shows has observed that, in general, the more educated the contestant, the less money he or she wins. To test her belief she gathers data about the last eight winners of her favorite game show. She records their winnings in dollars and the number of years of education. The results are as follows.
  
-Predict with 95% confidence the winnings of a contestant who has 10 years of education.

Accepted Answer

397.500 $\pm$179.971. Thus, LCL = $217.529, and UCL = $577.471.

Question 3

Trivia Games & Education: An ardent fan of television game shows has observed that, in general, the more educated the contestant, the less money he or she wins. To test her belief she gathers data about the last eight winners of her favorite game show. She records their winnings in dollars and the number of years of education. The results are as follows.
  
-Interpret the value of the slope of the regression line.

Accepted Answer

For each additional year of education a contestant has, his or her winnings on TV game shows decreases by an average of approximately $89.20.

Question 4

Do the $\rho$ and $\beta$1 tests in the previous two questions provide the same results? Explain.

Accepted Answer

Yes; both tests have the same value of t

Question 5

Wayne Newton Concert: At a recent Wayne Newton concert, a survey was conducted that asked a random sample of 20 people their age and how many concerts they have attended since the first of the year. The following data were collected:
   An Excel output follows:  
-Which interval in the previous two questions is narrower: the confidence interval estimate of the expected value of y or the prediction interval for the same given value of x (10 years) and same confidence level? Why?

Accepted Answer

The confidence interval estimate of the

Question 6

The symbol for the sample coefficient of correlation is:

Accepted Answer

A)  r 
B)  $\rho$ 
C)  r2 
D)  $\rho$2 
A)  r 
B)  $\rho$ 
C)  r2 
D)  $\rho$2

Question 7

Truck Speed vs Gas Mileage: An economist wanted to analyze the relationship between the speed of a car (x) and its gas mileage (y). As an experiment a car is operated at several different speeds and for each speed the gas mileage is measured. These data are shown below.
  
-The following 10 observations of variables x and y were collected.
   Find the least squares regression line, and the estimated value of y when x = 3.

Accepted Answer

The answer of Truck Speed vs Gas Mileage: An economist...

Question 8

For a regression analysis to be valid, the value of the error variable associated with any particular value of y is ____________________ of the value of the error variable associated with any other value of y.

Accepted Answer

The answer of For a regression analysis to be valid,...

Question 9

Sales and Experience: The general manager of a chain of department stores believes that experience is the most important factor in determining the level of success of a salesperson. To examine this belief she records last month's sales (in $1,000s) and the years of experience of 10 randomly selected salespeople. These data are listed below.
  
-Determine the coefficient of determination and discuss what its value tells you about the two variables.

Accepted Answer

R² = 0.9536, which means that 9

Question 10

The coefficient of correlation is used to determine:

Accepted Answer

A)  the strength and direction of the linear relationship between x and y. 
B)  the least squares estimates of the regression parameters. 
C)  the predicted value of y for a given value of x. 
D)  All of these choices. 
A)  the strength and direction of the linear relationship between x and y. 
B)  the least squares estimates of the regression parameters. 
C)  the predicted value of y for a given value of x. 
D)  All of these choices.

Question 11

The value of the sum of squares for regression SSR can never be smaller than 1.

Accepted Answer

A) True 
 B)False

Question 12

Allman Brothers Concert: At a recent Allman Brothers concert, a survey was conducted that asked a random sample of 20 people their age and how many concerts they have attended since the first of the year. The following data were collected:
   An Excel output follows:  
-Determine the least squares regression line.

Accepted Answer

The answer of Allman Brothers Concert: At a recent Allman...

Question 13

Sales and Experience: The general manager of a chain of department stores believes that experience is the most important factor in determining the level of success of a salesperson. To examine this belief she records last month's sales (in $1,000s) and the years of experience of 10 randomly selected salespeople. These data are listed below.
  
-Calculate the Pearson correlation coefficient. Interpret this result.

Accepted Answer

r = 0.9765. It has a positive

Question 14

If an estimated regression line has a y-intercept of 10 and a slope of 4, then when x = 2 the actual value of y is:

Accepted Answer

A)  18 
B)  15 
C)  14 
D)  unknown. 
A)  18 
B)  15 
C)  14 
D)  unknown.

Question 15

Car Speed and Gas Mileage: An economist wanted to analyze the relationship between the speed of a car (x) and its gas mileage (y). As an experiment a car is operated at several different speeds and for each speed the gas mileage is measured. These data are shown below.
  
-Predict with 99% confidence the gas mileage of a car traveling 55 mph.

Accepted Answer

31.236 @#LAT-DLM& 6.284. Thus,

Question 16

If the coefficient of determination is 0.95, this means that 95% of the y values were predicted correctly by the regression line.

Accepted Answer

A) True 
 B)False

Question 17

Allman Brothers Concert: At a recent Allman Brothers concert, a survey was conducted that asked a random sample of 20 people their age and how many concerts they have attended since the first of the year. The following data were collected:
   An Excel output follows:  
-Draw a scatter diagram of the data. Comment on whether it appears that a linear model might be appropriate to describe the relationship between the age and number of concerts attended by the respondents.

Accepted Answer

@#IMG-DLM& A linear model might be appro

Question 18

Sunshine and Melanoma: A medical researcher wanted to examine the relationship between the amount of sunshine (x) in hours, and incidence of melanoma, a type of skin cancer (y). As an experiment he found the number of melanoma cases detected per 100,000 of population and the average daily sunshine in eight counties around the country. These data are shown below.
  
-Estimate the number of skin cancer cases per 100,000 people who live in a state that gets 6 hours of sunshine on average.

Accepted Answer

The answer of Sunshine and Melanoma: A medical researcher wanted...

Question 19

The value of the sum of squares for regression SSR can never be smaller than 0.0.

Accepted Answer

A) True 
 B)False

Question 20

In a regression problem the following pairs of (x, y) are given: (3, 1), (3, -1), (3, 0), (3, -2) and (3, 2). That indicates that the:

Accepted Answer

A)  correlation coefficient is -1/2. 
B)  correlation coefficient is 0. 
C)  correlation coefficient is 1. 
D)  coefficient of determination is 3. 
A)  correlation coefficient is -1/2. 
B)  correlation coefficient is 0. 
C)  correlation coefficient is 1. 
D)  coefficient of determination is 3.

The symbol for the population coefficient of correlation is:

Do the $\rho$ and $\beta$ ₁ tests in the previous two questions provide the same results? Explain.

The symbol for the sample coefficient of correlation is:

For a regression analysis to be valid, the value of the error variable associated with any particular value of y is ____________________ of the value of the error variable associated with any other value of y.

The coefficient of correlation is used to determine:

The value of the sum of squares for regression SSR can never be smaller than 1.

If an estimated regression line has a y-intercept of 10 and a slope of 4, then when x = 2 the actual value of y is:

If the coefficient of determination is 0.95, this means that 95% of the y values were predicted correctly by the regression line.

The value of the sum of squares for regression SSR can never be smaller than 0.0.

In a regression problem the following pairs of (x, y) are given: (3, 1), (3, -1), (3, 0), (3, -2) and (3, 2). That indicates that the:

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical 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

Multiple Regression

Review of Statistical Inference

Filters

Exam 16: Simple Linear Regression and Correlation

The symbol for the population coefficient of correlation is:

Do the ρ\rhoρ and β\betaβ 1 tests in the previous two questions provide the same results? Explain.

The symbol for the sample coefficient of correlation is:

For a regression analysis to be valid, the value of the error variable associated with any particular value of y is ____________________ of the value of the error variable associated with any other value of y.

The coefficient of correlation is used to determine:

The value of the sum of squares for regression SSR can never be smaller than 1.

If an estimated regression line has a y-intercept of 10 and a slope of 4, then when x = 2 the actual value of y is:

If the coefficient of determination is 0.95, this means that 95% of the y values were predicted correctly by the regression line.

The value of the sum of squares for regression SSR can never be smaller than 0.0.

In a regression problem the following pairs of (x, y) are given: (3, 1), (3, -1), (3, 0), (3, -2) and (3, 2). That indicates that the:

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical 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

Multiple Regression

Review of Statistical Inference

Filters

Do the $\rho$ and $\beta$ ₁ tests in the previous two questions provide the same results? Explain.