Question 1

Which of the following is a violation of one of the major assumptions of the simple regression model?

Accepted Answer

A)  The error terms are independent of each other. 
B)  A histogram of the residuals forms a bell-shaped,symmetrical curve. 
C)  The error terms show no pattern. 
D)  As the value of x increases,the value of the error term also increases. 
A)  The error terms are independent of each other. 
B)  A histogram of the residuals forms a bell-shaped,symmetrical curve. 
C)  The error terms show no pattern. 
D)  As the value of x increases,the value of the error term also increases.

Question 2

What value of the Durbin-Watson statistic indicates that there is no autocorrelation present in time-ordered data?

Accepted Answer

A)  1 
B)  −1 
C)  2 
D)  −2 
E)  0 
A)  1 
B)  −1 
C)  2 
D)  −2 
E)  0

Question 3

Consider the following partial computer output from a simple linear regression analysis.   Determine the 95 percent confidence interval for the mean value of y when x = 9.00.Givens: ∑x = 129.03 and ∑x2 = 1178.547

Accepted Answer

[1.467,2.019]
When x = 9: y = 4.8615 + 9

Question 4

If there is significant autocorrelation present in a data set,the ________________ assumption is violated.

Accepted Answer

A)  normality 
B)  independence of error terms 
C)  μ = 0 
D)  constant variation 
A)  normality 
B)  independence of error terms 
C)  μ = 0 
D)  constant variation

Question 5

When using simple regression analysis,if there is a strong correlation between the independent and dependent variables,then we can conclude that an increase in the value of the independent variable causes an increase in the value of the dependent variable.

Accepted Answer

A) True 
 B)False

Question 6

A local tire dealer wants to predict the number of tires sold each month.He believes that the number of tires sold is a linear function of the amount of money invested in advertising.He randomly selects 6 months of data consisting of tire sales (in thousands of tires)and advertising expenditures (in thousands of dollars).Based on the data set with 6 observations,the simple linear regression model yielded the following results.   Determine the value of the estimated y-intercept.

Accepted Answer

The answer of A local tire dealer wants to predict...

Question 7

A local tire dealer wants to predict the number of tires sold each month.He believes that the number of tires sold is a linear function of the amount of money invested in advertising.He randomly selects 6 months of data consisting of tire sales (in thousands of tires)and advertising expenditures (in thousands of dollars).Based on the data set with 6 observations,the simple linear regression model yielded the following results.   Find the rejection point for the t statistic at α = .05 and test H0: β1 ≤ 0 vs.Ha: β1 > 0.

Accepted Answer

t_.05_,4 = 2.132;t = 2.645

Question 8

For a given data set,value of X,and confidence level,if all the other factors are constant,the confidence interval for the mean value of Y will ___________ be wider than the corresponding prediction interval for the individual value of Y.

Accepted Answer

A)  always 
B)  sometimes 
C)  never 
A)  always 
B)  sometimes 
C)  never

Question 9

For the same set of observations on a specified dependent variable,two different independent variables were used to develop two separate simple linear regression models.A portion of the results is presented below.   Based on the results given above,we can conclude that

Accepted Answer

A)  a prediction based on Model 1 is better than a prediction based on Model 2. 
B)  a prediction based on Model 2 is better than a prediction based on Model 1. 
C)  there is no difference in the predictive ability between Model 1 and Model 2. 
D)  there is not sufficient information to determine which of the two models is superior for prediction purposes. 
A)  a prediction based on Model 1 is better than a prediction based on Model 2. 
B)  a prediction based on Model 2 is better than a prediction based on Model 1. 
C)  there is no difference in the predictive ability between Model 1 and Model 2. 
D)  there is not sufficient information to determine which of the two models is superior for prediction purposes.

Question 10

Use the least squares regression equation 
= 12.36 + 4.745X and determine the predicted value of y when x = 3.25.

Accepted Answer

y = 27.78

Question 11

The notation Ŷ refers to the average value of the dependent variable Y.

Accepted Answer

A) True 
 B)False

Question 12

The _____ distribution is used for testing the significance of the slope term.

Accepted Answer

A)  t 
B)  z 
C)  r 
D)  r2 
A)  t 
B)  z 
C)  r 
D)  r2

Question 13

The correlation coefficient may assume any value between

Accepted Answer

A)  0 and 1. 
B)  −∞ and ∞. 
C)  0 and 8. 
D)  −1 and 1. 
E)  −1 and 0. 
A)  0 and 1. 
B)  −∞ and ∞. 
C)  0 and 8. 
D)  −1 and 1. 
E)  −1 and 0.

Question 14

An experiment was performed on a certain metal to determine if the strength is a function of heating time.Results based on 10 metal sheets are given below.Use the simple linear regression model.   Determine the value of the F statistic.

Accepted Answer

The answer of An experiment was performed on a certain...

Question 15

Consider the following partial computer output from a simple linear regression analysis.   What is the correlation coefficient?

Accepted Answer

r = −0.8536
Explained variance = Total v

Question 16

If the Durbin-Watson statistic is greater than (4 − dL),then we conclude that

Accepted Answer

A)  there is significant positive autocorrelation. 
B)  there is significant negative autocorrelation. 
C)  there is significant autocorrelation,but we cannot identify whether it is positive or negative. 
D)  the test result is inconclusive. 
A)  there is significant positive autocorrelation. 
B)  there is significant negative autocorrelation. 
C)  there is significant autocorrelation,but we cannot identify whether it is positive or negative. 
D)  the test result is inconclusive.

Question 17

Consider the following partial computer output from a simple linear regression analysis.   What is the estimated y-intercept?

Accepted Answer

The answer of Consider the following partial computer output from...

Question 18

Use the following results obtained from a simple linear regression analysis with 12 observations. 
= 37.2895 − (1.2024)X
r2 = .6744sb = .2934
Test to determine if there is a significant negative relationship between the independent and dependent variables at α = .05.Give the test statistic and the resulting conclusion.

Accepted Answer

Reject H₀,t = −4.10 There is a

Question 19

A data set with 7 observations yielded the following.Use the simple linear regression model.   Find the rejection point for the t statistic (α = .05).Test H0: β1 ≤ 0 vs.Ha: β1 > 0.

Accepted Answer

t = 13.6311;reject t

Question 20

If successive values of the residuals are close together,then there is a ___________ autocorrelation and the value of the Durbin-Watson statistic is _________.

Accepted Answer

A)  negative,large 
B)  positive,small 
C)  negative,small 
D)  positive,large 
A)  negative,large 
B)  positive,small 
C)  negative,small 
D)  positive,large

Which of the following is a violation of one of the major assumptions of the simple regression model?

What value of the Durbin-Watson statistic indicates that there is no autocorrelation present in time-ordered data?

Consider the following partial computer output from a simple linear regression analysis. Determine the 95 percent confidence interval for the mean value of y when x = 9.00.Givens: ∑x = 129.03 and ∑x² = 1178.547

If there is significant autocorrelation present in a data set,the ________________ assumption is violated.

When using simple regression analysis,if there is a strong correlation between the independent and dependent variables,then we can conclude that an increase in the value of the independent variable causes an increase in the value of the dependent variable.

For a given data set,value of X,and confidence level,if all the other factors are constant,the confidence interval for the mean value of Y will ___________ be wider than the corresponding prediction interval for the individual value of Y.

For the same set of observations on a specified dependent variable,two different independent variables were used to develop two separate simple linear regression models.A portion of the results is presented below. Based on the results given above,we can conclude that

Use the least squares regression equation = 12.36 + 4.745X and determine the predicted value of y when x = 3.25.

The notation Ŷ refers to the average value of the dependent variable Y.

The _____ distribution is used for testing the significance of the slope term.

The correlation coefficient may assume any value between

An experiment was performed on a certain metal to determine if the strength is a function of heating time.Results based on 10 metal sheets are given below.Use the simple linear regression model. Determine the value of the F statistic.

Consider the following partial computer output from a simple linear regression analysis. What is the correlation coefficient?

If the Durbin-Watson statistic is greater than (4 − d_L),then we conclude that

Consider the following partial computer output from a simple linear regression analysis. What is the estimated y-intercept?

A data set with 7 observations yielded the following.Use the simple linear regression model. Find the rejection point for the t statistic (α = .05).Test H₀: β₁ ≤ 0 vs.H_a: β₁ > 0.

If successive values of the residuals are close together,then there is a ___ autocorrelation and the value of the Durbin-Watson statistic is _.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences for Means and Proportions

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Exam 13: Chi-Square Tests

Which of the following is a violation of one of the major assumptions of the simple regression model?

What value of the Durbin-Watson statistic indicates that there is no autocorrelation present in time-ordered data?

Consider the following partial computer output from a simple linear regression analysis. Determine the 95 percent confidence interval for the mean value of y when x = 9.00.Givens: ∑x = 129.03 and ∑x2 = 1178.547

If there is significant autocorrelation present in a data set,the ________________ assumption is violated.

When using simple regression analysis,if there is a strong correlation between the independent and dependent variables,then we can conclude that an increase in the value of the independent variable causes an increase in the value of the dependent variable.

For a given data set,value of X,and confidence level,if all the other factors are constant,the confidence interval for the mean value of Y will ___________ be wider than the corresponding prediction interval for the individual value of Y.

For the same set of observations on a specified dependent variable,two different independent variables were used to develop two separate simple linear regression models.A portion of the results is presented below. Based on the results given above,we can conclude that

Use the least squares regression equation = 12.36 + 4.745X and determine the predicted value of y when x = 3.25.

The notation Ŷ refers to the average value of the dependent variable Y.

The _____ distribution is used for testing the significance of the slope term.

The correlation coefficient may assume any value between

An experiment was performed on a certain metal to determine if the strength is a function of heating time.Results based on 10 metal sheets are given below.Use the simple linear regression model. Determine the value of the F statistic.

Consider the following partial computer output from a simple linear regression analysis. What is the correlation coefficient?

If the Durbin-Watson statistic is greater than (4 − dL),then we conclude that

Consider the following partial computer output from a simple linear regression analysis. What is the estimated y-intercept?

A data set with 7 observations yielded the following.Use the simple linear regression model. Find the rejection point for the t statistic (α = .05).Test H0: β1 ≤ 0 vs.Ha: β1 > 0.

If successive values of the residuals are close together,then there is a ___________ autocorrelation and the value of the Durbin-Watson statistic is _________.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences for Means and Proportions

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Consider the following partial computer output from a simple linear regression analysis. Determine the 95 percent confidence interval for the mean value of y when x = 9.00.Givens: ∑x = 129.03 and ∑x² = 1178.547

If the Durbin-Watson statistic is greater than (4 − d_L),then we conclude that

A data set with 7 observations yielded the following.Use the simple linear regression model. Find the rejection point for the t statistic (α = .05).Test H₀: β₁ ≤ 0 vs.H_a: β₁ > 0.

If successive values of the residuals are close together,then there is a ___ autocorrelation and the value of the Durbin-Watson statistic is _.