Question 1

The regression line   has been fitted to the data points (4, 11), (2, 7), and (1, 5). The sum of squares for error will be 10.0.

Accepted Answer

A) True 
 B)False

Question 2

The symbol for the sample coefficient of correlation is:

Accepted Answer

A) r 
B) r 
C) r 2 
D) r 2 
A) r 
B) r 
C) r 2 
D) r 2

Question 3

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.   
 {Car Speed and Gas Mileage Narrative} Calculate the Pearson coefficient of correlation.

Accepted Answer

The answer of Car Speed and Gas Mileage An economist...

Question 4

An inverse relationship between an independent variable x and a dependent variably y means that as x increases, y decreases, and vice versa.

Accepted Answer

A) True 
 B)False

Question 5

Another name for the residual term in a regression equation is random error.

Accepted Answer

A) True 
 B)False

Question 6

The residuals are observations of the error variable e . Consequently, the minimized sum of squared deviations is called the sum of squares for error, denoted SSE.

Accepted Answer

A) True 
 B)False

Question 7

If the coefficient of correlation is - 0.60, then the coefficient of determination is:

Accepted Answer

A) - 0.60 
B) - 0.36 
C) 0.36 
D) 0.77 
A) - 0.60 
B) - 0.36 
C) 0.36 
D) 0.77

Question 8

The symbol for the population coefficient of correlation is:

Accepted Answer

A) r 
B) r 
C) r 2 
D) r 2 
A) r 
B) r 
C) r 2 
D) r 2

Question 9

In a simple linear regression problem, the following statistics are calculated from a sample of 10 observations:   . The least squares estimates of the slope and y -intercept are, respectively,

Accepted Answer

A) 1.5 and 0.5 
B) 2.5 and 1.5 
C) 1.5 and 2.5 
D) 2.5 and - 5.0 
A) 1.5 and 0.5 
B) 2.5 and 1.5 
C) 1.5 and 2.5 
D) 2.5 and - 5.0

Question 10

Game Show 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.   {Game Show Winnings & Education Narrative} Determine the coefficient of determination and discuss what its value tells you about the two variables.

Accepted Answer

R ² = 0.9185, which means that

Question 11

Statisticians have shown that sample y -intercept b 0 and sample slope coefficient b 1 are unbiased estimators of the population regression parameters b 0 and b 1, respectively.

Accepted Answer

A) True 
 B)False

Question 12

UV's and Skin Cancer A medical statistician wanted to examine the relationship between the amount of UV's ( x )and incidence of skin cancer ( y ). As an experiment he found the number of skin cancers detected per 100,000 of population and the average daily sunshine in eight states around the country. These data are shown below.   {UV's and Skin Cancer Narrative} Can we conclude at the 1% significance level that there is a linear relationship between sunshine and skin cancer?

Accepted Answer

H ₀: r = 0 vs. H ₁: r ¹ 0 Rejection region

Question 13

Graphically, a prediction interval is represented as two ____________________ lines.

Accepted Answer

The answer of Graphically, a prediction interval is represented as...

Question 14

The sample correlation coefficient between x and y is 0.375. It has been found out that the p -value is 0.256 when testing H 0: r = 0 against the two-sided alternative H 1: r ¹ 0. To test H 0: r = 0 against the one-sided alternative H 1: r > 0 at a significant level of 0.193, the p- value will be equal to

Accepted Answer

A) 0.128 
B) 0.512 
C) 0.744 
D) 0.872 
A) 0.128 
B) 0.512 
C) 0.744 
D) 0.872

Question 15

A confidence interval (as opposed to a prediction interval)is used to estimate the long-run average value of y .

Accepted Answer

A) True 
 B)False

Question 16

Which of the following statistics and procedures can be used to determine whether a linear model should be employed?

Accepted Answer

A) The standard error of estimate. 
B) The coefficient of determination. 
C) The t -test of the slope. 
D) All of these choices are true. 
A) The standard error of estimate. 
B) The coefficient of determination. 
C) The t -test of the slope. 
D) All of these choices are true.

Question 17

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.   {Car Speed and Gas Mileage Narrative} Calculate the coefficient of determination and interpret its value.

Accepted Answer

R ² = 0.95. This means that 95%

Question 18

Sales and Experience The general manager of a chain of hardware 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.   {Sales and Experience Narrative} Determine the standard error of estimate and describe what this statistic tells you about the regression line.

Accepted Answer

s_e = 1.5724

The regression line has been fitted to the data points (4, 11), (2, 7), and (1, 5). The sum of squares for error will be 10.0.

The symbol for the sample coefficient of correlation is:

An inverse relationship between an independent variable x and a dependent variably y means that as x increases, y decreases, and vice versa.

Another name for the residual term in a regression equation is random error.

The residuals are observations of the error variable e . Consequently, the minimized sum of squared deviations is called the sum of squares for error, denoted SSE.

If the coefficient of correlation is - 0.60, then the coefficient of determination is:

The symbol for the population coefficient of correlation is:

In a simple linear regression problem, the following statistics are calculated from a sample of 10 observations: . The least squares estimates of the slope and y -intercept are, respectively,

Statisticians have shown that sample y -intercept b ₀ and sample slope coefficient b ₁ are unbiased estimators of the population regression parameters b ₀ and b ₁, respectively.

Graphically, a prediction interval is represented as two ____________________ lines.

A confidence interval (as opposed to a prediction interval)is used to estimate the long-run average value of y .

Which of the following statistics and procedures can be used to determine whether a linear model should be employed?

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 Populat

Inference About Comparing Two Populat

Analysis of Variance

Chi-Squared Tests

Multiple Regression

Review of Statistical Inference

Filters

Exam 16: Simple Linear Regression and Correlat

The regression line has been fitted to the data points (4, 11), (2, 7), and (1, 5). The sum of squares for error will be 10.0.

The symbol for the sample coefficient of correlation is:

An inverse relationship between an independent variable x and a dependent variably y means that as x increases, y decreases, and vice versa.

Another name for the residual term in a regression equation is random error.

The residuals are observations of the error variable e . Consequently, the minimized sum of squared deviations is called the sum of squares for error, denoted SSE.

If the coefficient of correlation is - 0.60, then the coefficient of determination is:

The symbol for the population coefficient of correlation is:

In a simple linear regression problem, the following statistics are calculated from a sample of 10 observations: . The least squares estimates of the slope and y -intercept are, respectively,

Statisticians have shown that sample y -intercept b 0 and sample slope coefficient b 1 are unbiased estimators of the population regression parameters b 0 and b 1, respectively.

Graphically, a prediction interval is represented as two ____________________ lines.

A confidence interval (as opposed to a prediction interval)is used to estimate the long-run average value of y .

Which of the following statistics and procedures can be used to determine whether a linear model should be employed?

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 Populat

Inference About Comparing Two Populat

Analysis of Variance

Chi-Squared Tests

Multiple Regression

Review of Statistical Inference

Filters

Statisticians have shown that sample y -intercept b ₀ and sample slope coefficient b ₁ are unbiased estimators of the population regression parameters b ₀ and b ₁, respectively.