Question 1

In residual analysis,as the value of the leverage _____________,the value of the studentized residual _____________.

Accepted Answer

A) Decreases,increases 
B) Increases,decreases 
C) Decreases,decreases 
D) None of the above 
A) Decreases,increases 
B) Increases,decreases 
C) Decreases,decreases 
D) None of the above

Question 2

A multiple linear regression analysis involving 45 observations resulted in the following least squares prediction equation:

Accepted Answer

.
The SSE for the above model is 49.
Add

Question 3

An independent variable dropped during an iteration of the backward elimination process may be added back to the regression model during a later iteration of the process.

Accepted Answer

A) True 
 B)False

Question 4

In multiple regression analysis an outlier observation is ____________ influential.

Accepted Answer

A) Always 
B) Sometimes 
C) Never 
A) Always 
B) Sometimes 
C) Never

Question 5

In the quadratic regression model y = $\beta$0 + $\beta$1x + $\beta$2x2 + $\varepsilon$,if the value of the term $\beta$1 increases,then the parabola shifts _________.

Accepted Answer

A) Left 
B) Right 
C) Up 
D) Down 
A) Left 
B) Right 
C) Up 
D) Down

Question 6

If a multiple regression model has a(n)_____ statistic substantially greater than k + 1,then it can be shown that this model has substantial bias and is undesirable.

Accepted Answer

A) C 
B) F 
C) Cook's distance 
D) Durbin-Watson 
A) C 
B) F 
C) Cook's distance 
D) Durbin-Watson

Question 7

In converting the residual to a studentized (standardized)residual for a given observation,the residual for the observation is divided by the residual's __________.

Accepted Answer

A) sample size 
B) t value 
C) standard error 
D) square 
A) sample size 
B) t value 
C) standard error 
D) square

Question 8

Based on 25 time ordered observations from a multiple regression model with 3 independent variables,we have determined the Durbin-Watson statistic,d = 1.29.At $\alpha$ = .05,test to determine if there is any evidence of positive autocorrelation? State your conclusions.

Accepted Answer

No because 1.12 < 1.

Question 9

If the Durbin-Watson statistic is less than dL,then it is concluded that

Accepted Answer

A) There is significant positive autocorrelation. 
B) There is significant negative autocorrelation. 
C) There is significant autocorrelation but it cannot be identified whether it is positive or negative. 
D) The test results are inconclusive. 
A) There is significant positive autocorrelation. 
B) There is significant negative autocorrelation. 
C) There is significant autocorrelation but it cannot be identified whether it is positive or negative. 
D) The test results are inconclusive.

Question 10

An overall measure of the difference between the least squares point estimates calculated using observation i,and the least squares point estimates calculated without using observation i is called the ____________ measure.

Accepted Answer

A) Durbin-Watson 
B) Cook's distance 
C) R2 
D) C 
A) Durbin-Watson 
B) Cook's distance 
C) R2 
D) C

Question 11

The graph of the prediction equation obtained from the model   is a(n)

Accepted Answer

A) Line 
B) Plane 
C) Parabola 
D) Exponential curve 
A) Line 
B) Plane 
C) Parabola 
D) Exponential curve

Question 12

If the simple correlation coefficient between two independent variables is greater than .90,then ______________________ is considered to be severe.

Accepted Answer

A) autocorrelation 
B) interaction 
C) multicollinearity 
D) coefficient of determination 
A) autocorrelation 
B) interaction 
C) multicollinearity 
D) coefficient of determination

Question 13

Stepwise regression uses a series of _____ tests during each iteration in order to determine which independent variables should be brought into the regression model.

Accepted Answer

A) C 
B) F 
C) t 
D) VIF 
A) C 
B) F 
C) t 
D) VIF

Question 14

Multicollinearity is severe if the largest variance inflation factor (VIF)is greater than _____.

Accepted Answer

A) 100 
B) 5 
C) 10 
D) 1 
A) 100 
B) 5 
C) 10 
D) 1

Question 15

A multiple regression model was applied to a data set with 8 time ordered observations.The residuals for these observations are given below.   Calculate the value of MSE and the standard error.

Accepted Answer

The answer of A multiple regression model was applied to...

Question 16

In a multiple regression analysis,the current model has three independent variables.The analyst decides to add another (fourth)independent variable while retaining the other three independent variables.As a result of this addition,the value of MSE will ____________ decrease.

Accepted Answer

A) Always 
B) Sometimes 
C) Never 
A) Always 
B) Sometimes 
C) Never

Question 17

In a multiple regression mode if the largest VIF is 21.6,then it can be concluded that there are indications of multicollinearity.

Accepted Answer

A) True 
 B)False

Question 18

A county has four major hospitals: 1)Regional Memorial;2)General;3)Charity;and 4)City.A multiple regression model is used to compare the time spent in the hospital after a heart by-pass surgery among the four hospitals.The response variable is the amount of time spent in the hospital (in days),the quantitative independent variables include the age of the patient,cholesterol level of the patient,and blood pressure of the patient.Define the dummy variables so that all other hospitals are compared to the City hospital (base).

Accepted Answer

x₁ = 1,if the heart surgery is in Regiona

Question 19

If the multiple coefficient of determination that relates x1 to all the other independent variables,R2(x1)= .25,calculate the variance inflation factor for x1.Should the analyst be concerned about multicollinearity? Why?

Accepted Answer

1.33.No,the analyst

Question 20

Multicollinearity between independent variables is serious if the mean variance inflation factor is

Accepted Answer

A) Substantially less than 1 
B) Substantially greater than 1 
C) Between - 1 and + 1 
D) Less than .5 
E) Substantially less than zero 
A) Substantially less than 1 
B) Substantially greater than 1 
C) Between - 1 and + 1 
D) Less than .5 
E) Substantially less than zero

In residual analysis,as the value of the leverage _,the value of the studentized residual _.

A multiple linear regression analysis involving 45 observations resulted in the following least squares prediction equation:

An independent variable dropped during an iteration of the backward elimination process may be added back to the regression model during a later iteration of the process.

In multiple regression analysis an outlier observation is ____________ influential.

In the quadratic regression model y = $\beta$ ₀ + $\beta$ ₁x + $\beta$ ₂x² + $\varepsilon$ ,if the value of the term $\beta$ ₁ increases,then the parabola shifts _________.

If a multiple regression model has a(n)_____ statistic substantially greater than k + 1,then it can be shown that this model has substantial bias and is undesirable.

In converting the residual to a studentized (standardized)residual for a given observation,the residual for the observation is divided by the residual's __________.

Based on 25 time ordered observations from a multiple regression model with 3 independent variables,we have determined the Durbin-Watson statistic,d = 1.29.At $\alpha$ = .05,test to determine if there is any evidence of positive autocorrelation? State your conclusions.

If the Durbin-Watson statistic is less than d_L,then it is concluded that

An overall measure of the difference between the least squares point estimates calculated using observation i,and the least squares point estimates calculated without using observation i is called the ____________ measure.

The graph of the prediction equation obtained from the model is a(n)

If the simple correlation coefficient between two independent variables is greater than .90,then ______________________ is considered to be severe.

Stepwise regression uses a series of _____ tests during each iteration in order to determine which independent variables should be brought into the regression model.

Multicollinearity is severe if the largest variance inflation factor (VIF)is greater than _____.

A multiple regression model was applied to a data set with 8 time ordered observations.The residuals for these observations are given below. Calculate the value of MSE and the standard error.

In a multiple regression analysis,the current model has three independent variables.The analyst decides to add another (fourth)independent variable while retaining the other three independent variables.As a result of this addition,the value of MSE will ____________ decrease.

In a multiple regression mode if the largest VIF is 21.6,then it can be concluded that there are indications of multicollinearity.

If the multiple coefficient of determination that relates x₁ to all the other independent variables,R²(x₁)= .25,calculate the variance inflation factor for x₁.Should the analyst be concerned about multicollinearity? Why?

Multicollinearity between independent variables is serious if the mean variance inflation factor 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 Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression

Time Series Forecasting

Process Improvement Using Control Charts

Nonparametric Methods

Decision Theory

Filters

Exam 15: Model Building and Model Diagnostics

In residual analysis,as the value of the leverage _____________,the value of the studentized residual _____________.

A multiple linear regression analysis involving 45 observations resulted in the following least squares prediction equation:

An independent variable dropped during an iteration of the backward elimination process may be added back to the regression model during a later iteration of the process.

In multiple regression analysis an outlier observation is ____________ influential.

In the quadratic regression model y = β\betaβ 0 + β\betaβ 1x + β\betaβ 2x2 + ε\varepsilonε ,if the value of the term β\betaβ 1 increases,then the parabola shifts _________.

If a multiple regression model has a(n)_____ statistic substantially greater than k + 1,then it can be shown that this model has substantial bias and is undesirable.

In converting the residual to a studentized (standardized)residual for a given observation,the residual for the observation is divided by the residual's __________.

Based on 25 time ordered observations from a multiple regression model with 3 independent variables,we have determined the Durbin-Watson statistic,d = 1.29.At α\alphaα = .05,test to determine if there is any evidence of positive autocorrelation? State your conclusions.

If the Durbin-Watson statistic is less than dL,then it is concluded that

An overall measure of the difference between the least squares point estimates calculated using observation i,and the least squares point estimates calculated without using observation i is called the ____________ measure.

The graph of the prediction equation obtained from the model is a(n)

If the simple correlation coefficient between two independent variables is greater than .90,then ______________________ is considered to be severe.

Stepwise regression uses a series of _____ tests during each iteration in order to determine which independent variables should be brought into the regression model.

Multicollinearity is severe if the largest variance inflation factor (VIF)is greater than _____.

A multiple regression model was applied to a data set with 8 time ordered observations.The residuals for these observations are given below. Calculate the value of MSE and the standard error.

In a multiple regression analysis,the current model has three independent variables.The analyst decides to add another (fourth)independent variable while retaining the other three independent variables.As a result of this addition,the value of MSE will ____________ decrease.

In a multiple regression mode if the largest VIF is 21.6,then it can be concluded that there are indications of multicollinearity.

If the multiple coefficient of determination that relates x1 to all the other independent variables,R2(x1)= .25,calculate the variance inflation factor for x1.Should the analyst be concerned about multicollinearity? Why?

Multicollinearity between independent variables is serious if the mean variance inflation factor 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 Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression

Time Series Forecasting

Process Improvement Using Control Charts

Nonparametric Methods

Decision Theory

Filters

In residual analysis,as the value of the leverage _,the value of the studentized residual _.

In the quadratic regression model y = $\beta$ ₀ + $\beta$ ₁x + $\beta$ ₂x² + $\varepsilon$ ,if the value of the term $\beta$ ₁ increases,then the parabola shifts _________.

Based on 25 time ordered observations from a multiple regression model with 3 independent variables,we have determined the Durbin-Watson statistic,d = 1.29.At $\alpha$ = .05,test to determine if there is any evidence of positive autocorrelation? State your conclusions.

If the Durbin-Watson statistic is less than d_L,then it is concluded that

If the multiple coefficient of determination that relates x₁ to all the other independent variables,R²(x₁)= .25,calculate the variance inflation factor for x₁.Should the analyst be concerned about multicollinearity? Why?