Question 1

Which of the following is NOT an assumption for the simple linear regression model?

Accepted Answer

A)  The individual error terms are statistically independent. 
B)  The distribution of the error terms will be skewed left or right depending on the shape of the dependent variable. 
C)  The error terms have equal variances for all values of the independent variable. 
D)  The mean of the dependent variable value for all levels of x can be connected by a straight line. 
A)  The individual error terms are statistically independent. 
B)  The distribution of the error terms will be skewed left or right depending on the shape of the dependent variable. 
C)  The error terms have equal variances for all values of the independent variable. 
D)  The mean of the dependent variable value for all levels of x can be connected by a straight line.

Question 2

A study was recently performed by the Internal Revenue Service to determine how much tip income waiters and waitresses should make based on the size of the bill at each table. A random sample of bills and resulting tips were collected and the following regression results were observed: SUMMARY OUTPUT   Given this output, the point estimate for the average tip per dollar amount of the bill is approximately $0.21.

Accepted Answer

A) True 
 B)False

Question 3

In a study of 30 customers' utility bills in which the monthly bill was the dependent variable and the number of square feet in the house is the independent variable, the resulting regression model is = 23.40 + 0.4x. Given this, the sample correlation coefficient is known to be positive.

Accepted Answer

A) True 
 B)False

Question 4

Use the following regression results to answer the question below.   Which of the following is true?

Accepted Answer

A)  x explains about 88.5 percent of the variation in y. 
B)  y explains about 88.5 percent of the variation in x. 
C)  x explains about 78.4 percent of the variation in y. 
D)  y explains about 78.4 percent of the variation in x. 
A)  x explains about 88.5 percent of the variation in y. 
B)  y explains about 88.5 percent of the variation in x. 
C)  x explains about 78.4 percent of the variation in y. 
D)  y explains about 78.4 percent of the variation in x.

Question 5

If a residual plot exhibits a curved pattern in the residuals, this means that:

Accepted Answer

A)  the errors are not normally distributed. 
B)  there must be a curvilinear relation between x and y. 
C)  there is no significant relation between x and y. 
D)  there is a problem with constant variance. 
A)  the errors are not normally distributed. 
B)  there must be a curvilinear relation between x and y. 
C)  there is no significant relation between x and y. 
D)  there is a problem with constant variance.

Question 6

The sign on the intercept coefficient in a simple regression model will always be the same as the sign on the correlation coefficient.

Accepted Answer

A) True 
 B)False

Question 7

A correlation of -0.9 indicates a weak linear relationship between the variables.

Accepted Answer

A) True 
 B)False

Question 8

The following regression output is available. Notice that some of the values are missing.   Given this information, what percent of the variation in the y variable is explained by the independent variable?

Accepted Answer

A)  About 75 percent 
B)  Approximately 57 percent 
C)  Can't be determined without having the actual data available. 
D)  About 25 percent 
A)  About 75 percent 
B)  Approximately 57 percent 
C)  Can't be determined without having the actual data available. 
D)  About 25 percent

Question 9

When the intercept in a regression equation is deemed not significantly different from 0, then in making predictions for y, 0.0 should be used as the value of the intercept rather than the estimated intercept value.

Accepted Answer

A) True 
 B)False

Question 10

Assuming that a regression has been conducted for a group of small companies where x = the number of employees at the company, y = annual revenue of the company (recorded in thousands of dollars), and the largest company included in the study had 82 employees. The resulting regression equation is = 59.2 + 83.4x. Which of the following is true?

Accepted Answer

A)  For each additional employee, revenue on average will increase by $83.4 
B)  A company with 2100 employees could be predicted to have average revenue of about $175 million. 
C)  For each additional employee, revenue on average will increase by $59.2 thousand. 
D)  This model should not be used to make predictions for companies with more than 82 employees. 
A)  For each additional employee, revenue on average will increase by $83.4 
B)  A company with 2100 employees could be predicted to have average revenue of about $175 million. 
C)  For each additional employee, revenue on average will increase by $59.2 thousand. 
D)  This model should not be used to make predictions for companies with more than 82 employees.

Question 11

Consider the following partially completed computer printout for a regression analysis where the dependent variable is the price of a personal computer and the independent variable is the size of the hard drive.   Based on the information provided, what percentage of the variation in the price of the personal computers is accounted for by the regression model using hard drive capacity as the independent variable?

Accepted Answer

A)  About 82 percent 
B)  About 67 percent 
C)  217.75 
D)  About 66 percent 
A)  About 82 percent 
B)  About 67 percent 
C)  217.75 
D)  About 66 percent

Question 12

Given the data below, one ran the simple regression analysis of Y on X.   The relationship between Y and X is

Accepted Answer

A)  significant at the alpha = 1 percent level. 
B)  significant at the alpha = 5 percent level. 
C)  significant at the alpha = 10 percent level. 
D)  not significant at the alpha = 10 percent level. 
A)  significant at the alpha = 1 percent level. 
B)  significant at the alpha = 5 percent level. 
C)  significant at the alpha = 10 percent level. 
D)  not significant at the alpha = 10 percent level.

Question 13

In a simple linear regression analysis, if the test statistic for testing the significance of the regression slope coefficient is 3.6, the F ratio from the analysis of variance table is known to be 12.96

Accepted Answer

A) True 
 B)False

Question 14

If the correlation between two variables in a simple linear regression model is calculated to be .73, the R-square value is .85.

Accepted Answer

A) True 
 B)False

Question 15

Explain what is meant by the term least squares regression model.

Accepted Answer

When we look at a scatter plot, we see t

Question 16

A university study indicated that a correlation of -0.7 was found between the number of hours spent playing video games and a student's GPA. This means that the more time spent playing video games, the lower the overall GPA.

Accepted Answer

A) True 
 B)False

Question 17

A bank is interested in determining whether its customers' checking balances are linearly related to their savings balances. A sample of n = 20 customers was selected and the correlation was calculated to be +0.40. If the bank is interested in testing to see whether there is a significant linear relationship between the two variables using a significance level of .05, the correct null and alternative hypotheses to test are: H0 : r = 0.0 Ha : r ≠ 0.0

Accepted Answer

A) True 
 B)False

Question 18

The values of the regression coefficients are found such the sum of the residuals is minimized.

Accepted Answer

A) True 
 B)False

Question 19

Given the following regression equation, the predicted value for y when x = 0.5 is about 4.57

Accepted Answer

A) True 
 B)False

Which of the following is NOT an assumption for the simple linear regression model?

In a study of 30 customers' utility bills in which the monthly bill was the dependent variable and the number of square feet in the house is the independent variable, the resulting regression model is = 23.40 + 0.4x. Given this, the sample correlation coefficient is known to be positive.

Use the following regression results to answer the question below. Which of the following is true?

If a residual plot exhibits a curved pattern in the residuals, this means that:

The sign on the intercept coefficient in a simple regression model will always be the same as the sign on the correlation coefficient.

A correlation of -0.9 indicates a weak linear relationship between the variables.

The following regression output is available. Notice that some of the values are missing. Given this information, what percent of the variation in the y variable is explained by the independent variable?

When the intercept in a regression equation is deemed not significantly different from 0, then in making predictions for y, 0.0 should be used as the value of the intercept rather than the estimated intercept value.

Given the data below, one ran the simple regression analysis of Y on X. The relationship between Y and X is

In a simple linear regression analysis, if the test statistic for testing the significance of the regression slope coefficient is 3.6, the F ratio from the analysis of variance table is known to be 12.96

If the correlation between two variables in a simple linear regression model is calculated to be .73, the R-square value is .85.

Explain what is meant by the term least squares regression model.

A university study indicated that a correlation of -0.7 was found between the number of hours spent playing video games and a student's GPA. This means that the more time spent playing video games, the lower the overall GPA.

The values of the regression coefficients are found such the sum of the residuals is minimized.

Given the following regression equation, the predicted value for y when x = 0.5 is about 4.57

The Where, Why, and How of Data Collection

Graphs, Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introducing Business Analytics

Introduction to Decision Analysis

Introduction to Quality and Statistical Process Control

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Exam 14: Introduction to Linear Regression and Correlation Analysis

Which of the following is NOT an assumption for the simple linear regression model?

In a study of 30 customers' utility bills in which the monthly bill was the dependent variable and the number of square feet in the house is the independent variable, the resulting regression model is = 23.40 + 0.4x. Given this, the sample correlation coefficient is known to be positive.

Use the following regression results to answer the question below. Which of the following is true?

If a residual plot exhibits a curved pattern in the residuals, this means that:

The sign on the intercept coefficient in a simple regression model will always be the same as the sign on the correlation coefficient.

A correlation of -0.9 indicates a weak linear relationship between the variables.

The following regression output is available. Notice that some of the values are missing. Given this information, what percent of the variation in the y variable is explained by the independent variable?

When the intercept in a regression equation is deemed not significantly different from 0, then in making predictions for y, 0.0 should be used as the value of the intercept rather than the estimated intercept value.

Given the data below, one ran the simple regression analysis of Y on X. The relationship between Y and X is

In a simple linear regression analysis, if the test statistic for testing the significance of the regression slope coefficient is 3.6, the F ratio from the analysis of variance table is known to be 12.96

If the correlation between two variables in a simple linear regression model is calculated to be .73, the R-square value is .85.

Explain what is meant by the term least squares regression model.

A university study indicated that a correlation of -0.7 was found between the number of hours spent playing video games and a student's GPA. This means that the more time spent playing video games, the lower the overall GPA.

The values of the regression coefficients are found such the sum of the residuals is minimized.

Given the following regression equation, the predicted value for y when x = 0.5 is about 4.57

The Where, Why, and How of Data Collection

Graphs, Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introducing Business Analytics

Introduction to Decision Analysis

Introduction to Quality and Statistical Process Control

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