Question 1

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

Accepted Answer

A)  coefficient of correlation is -1. 
B)  coefficient of correlation is 0. 
C)  coefficient of correlation is 1. 
D)  coefficient of determination is between -1 and 1. 
A)  coefficient of correlation is -1. 
B)  coefficient of correlation is 0. 
C)  coefficient of correlation is 1. 
D)  coefficient of determination is between -1 and 1. B

Question 2

Consider the following data values of variables x and y
 $$\begin{array} { | l | l | l | l | l | l | } 
\hline \mathbf { x } & 4 & 2 & 6 & 4 & 3 \
\hline \mathbf { y } & 5 & 3 & 7 & 6 & 5 \
\hline
\end{array}$$ Use Excel or Minitab to construct a scatter diagram of the data points

Accepted Answer

The answer of Consider the following data values of variables...

Question 3

A regression analysis between weight (y in pounds)and height (x in inches)resulted in the following least squares line: $\hat{y}$ = 120 + 5x.This implies that if the height is increased by 1 inch,the weight is expected to:

Accepted Answer

A)  increase by 1 pound. 
B)  decrease by 1 pound. 
C)  increase by 5 pounds. 
D)  decrease by 24 pounds. 
A)  increase by 1 pound. 
B)  decrease by 1 pound. 
C)  increase by 5 pounds. 
D)  decrease by 24 pounds. C

Question 4

At the 0.05 level of significance,test the null hypothesis that the population coefficient of correlation is really zero. $$\begin{array} { l } 
H _ { 0 } : p = 0 \
H _ { 1 } : p \neq 0
\end{array}$$

Accepted Answer

If |t| > 2.571,we reject the null hypoth

Question 5

For the values of the coefficient of determination listed below,which one implies the greatest value of SSR (regression sum of squares)given that SST = 500?

Accepted Answer

A)  0.95 
B)  -1.00 
C)  0.28 
D)  0.00 
E)  -0.88 
A)  0.95 
B)  -1.00 
C)  0.28 
D)  0.00 
E)  -0.88

Question 6

GPA
The following table shows the grade point average (GPA)for 5 students along with their entrance exam scores for MBA programs (GMAT).Develop a model that would predict the GPA of a student based on their GMAT score.
 $$\begin{array} { | c | c | c } 
\hline \text { Student } & \text { CPA } & \text { GMAT } \
\hline 1 & 3.5 & 6.7 \
\hline 2 & 3.1 & 5.4 \
\hline 3 & 3.2 & 4.8 \
\hline 4 & 4.0 & 7.0 \
\hline 5 & 3.6 & 5.9 \
\hline 6 & 3.2 & 5.2 \
\hline 7 & 3.7 & 7.2 \
\hline
\end{array}$$
-Construct a 95% confidence interval for the mean GPA when GMAT = 6.5.

Accepted Answer

When x = 6.5, @#LAT-DLM& .Also t._025,5 = 2.57

Question 7

Maintenance Costs
Data was collected to investigate the relationship between the age and annual maintenance costs for a one particular car.The table below shows the costs over the life of a seven-year old car.
 $$\begin{array} { | c | c } 
\hline \text { Year } & \text { Annual Maintenance Casts } \
\hline 1 & \$ 150 \
\hline 2 & \$ 210 \
\hline 3 & \$ 450 \
\hline 4 & \$ 490 \
\hline 5 & \$ 510 \
\hline 6 & \$ 1590 \
\hline 7 & \$ 160 \
\hline
\end{array}$$
-Calculate the coefficient of determination and interpret the results.

Accepted Answer

@#LAT-DLM& . This means that 73.1% of th

Question 8

Household
The following data was collected by a particular company to determine if a relationship exists between the number of people in a household and weekly food expenditures.
 $$\begin{array} { | c | c | c } 
\hline \text { Househald } & \text { Number in Hausehald } & \text { Weakly Fadd Expenses } \
\hline 1 & 2 & \$ 95 \
\hline 2 & 3 & \$ 137 \
\hline 3 & 5 & \$ 165 \
\hline 4 & 2 & \$ 105 \
\hline 5 & 4 & \$ 227 \
\hline 6 & 4 & \$ 240 \
\hline 7 & 5 & \$ 185 \
\hline
\end{array}$$
-Construct a 95% prediction interval for the mean weekly food expense when the number in household equals 3.

Accepted Answer

When x = 3, @#LAT-DLM& .Also t._025,5 = 2.571.

Question 9

Number of years
Data was collected to describe the relationship between salary and number of years of working experience at a particular organization and is shown below in the following table.
 $$\begin{array} { | c | c | c | } 
\hline \text { Employee } & \text { Salary } & \text { Years af Experience } \
\hline 1 & \$ 35,000 & 4 \
\hline 2 & \$ 7,200 & 13 \
\hline 3 & \$ 45,900 & 6 \
\hline 4 & \$ 42,200 & 7 \
\hline 5 & \$ 65,600 & 10 \
\hline 6 & \$ 51,500 & 9 \
\hline 7 & \$ 57,200 & 5 \
\hline 8 & \$ 71,400 & 7 \
\hline
\end{array}$$
-Find the least-squares regression line.

Accepted Answer

The answer of Number of years
Data was collected to describe...

Question 10

Salesperson
The general manager of a chain of furniture 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.
 $$\begin{array} { | c | c | c | } 
\hline \text { Ealesperson } & \text { Years of Experience } & \text { Eales } \
\hline 1 & 0 & 7 \
\hline 2 & 2 & 9 \
\hline 3 & 10 & 20 \
\hline 4 & 3 & 15 \
\hline 5 & 8 & 18 \
\hline 0 & 5 & 14 \
\hline 7 & 12& 20 \
\hline 8 &7 & 17 \
\hline 9 &20 & 30 \
\hline 10 & 15& 25 \
\hline
\end{array}$$
-Predict with 95% confidence the average monthly sales of all salespersons with 10 years of experience.
95% CI10 yrs + = ________________
Enter as (n1,n2)with no $ or "," in the number.

Accepted Answer

The answer of Salesperson
The general manager of a chain of...

Question 11

What is residual analysis,and what information can it provide?

Accepted Answer

Residual analysis refers to a broad clas

Question 12

In a simple linear model,testing whether the slope of the population regression line is zero is the same as testing whether or not the population ____________________ equals zero.

Accepted Answer

coefficien

Question 13

Salesperson
The general manager of a chain of furniture 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.
 $$\begin{array} { | c | c | c | } 
\hline \text { Ealesperson } & \text { Years of Experience } & \text { Eales } \
\hline 1 & 0 & 7 \
\hline 2 & 2 & 9 \
\hline 3 & 10 & 20 \
\hline 4 & 3 & 15 \
\hline 5 & 8 & 18 \
\hline 0 & 5 & 14 \
\hline 7 & 12& 20 \
\hline 8 &7 & 17 \
\hline 9 &20 & 30 \
\hline 10 & 15& 25 \
\hline
\end{array}$$
-If the regression equation is $\hat { y } = 8.63 + 1.0817 x$ ,calculate the residuals

Accepted Answer

The residuals are: -

Question 14

If the standard error of estimate  5yx = 18 and n = 10, then the error sum of squares, SSE, is:

Accepted Answer

A) 2916. 
B) 2592. 
C) 1800. 
D) 3240. 
A) 2916. 
B) 2592. 
C) 1800. 
D) 3240.

Question 15

Salesperson
The general manager of a chain of furniture 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.
 $$\begin{array} { | c | c | c | } 
\hline \text { Ealesperson } & \text { Years of Experience } & \text { Eales } \
\hline 1 & 0 & 7 \
\hline 2 & 2 & 9 \
\hline 3 & 10 & 20 \
\hline 4 & 3 & 15 \
\hline 5 & 8 & 18 \
\hline 0 & 5 & 14 \
\hline 7 & 12& 20 \
\hline 8 &7 & 17 \
\hline 9 &20 & 30 \
\hline 10 & 15& 25 \
\hline
\end{array}$$
-If the regression equation is $\hat { y } = 8.63 + 1.0817 x$ ,determine the predicted values of y.

Accepted Answer

The @#LAT-DLM& values are: 8.6

Question 16

The vertical spread of the data points about the regression line is measured by the:

Accepted Answer

A)  regression coefficient. 
B)  standard error of estimate. 
C)  y-intercept. 
D)  homoscedasticity coefficient. 
E)  t-ratio. 
A)  regression coefficient. 
B)  standard error of estimate. 
C)  y-intercept. 
D)  homoscedasticity coefficient. 
E)  t-ratio.

Question 17

For a given value of x,which will be wider,a 90% confidence interval or a 90% prediction interval? Explain

Accepted Answer

For a given value of s,the prediction in

Question 18

The number of degrees of freedom associated with the standard error of estimate is

Accepted Answer

A)  n-1 since only the slope is estimated from sample data. 
B)  n-1 since only the intercept is estimated from sample data. 
C)  n-1 since only the predicted value of y is estimated from sample data. 
D)  n-2 since the slope and the intercept are estimated from sample data. 
A)  n-1 since only the slope is estimated from sample data. 
B)  n-1 since only the intercept is estimated from sample data. 
C)  n-1 since only the predicted value of y is estimated from sample data. 
D)  n-2 since the slope and the intercept are estimated from sample data.

Question 19

Another name for the residual term in a regression equation is:

Accepted Answer

A)  random error. 
B)  heteroscedasticity. 
C)  homoscedasticity. 
D)  pooled variances. 
E)  residual analysis. 
A)  random error. 
B)  heteroscedasticity. 
C)  homoscedasticity. 
D)  pooled variances. 
E)  residual analysis.

Question 20

Briefly describe each of the following:
a)Homoscedasticity
b)Residual

Accepted Answer

a)The assumption of equal popu

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

Consider the following data values of variables x and y 4 2 6 4 3 5 3 7 6 5 Use Excel or Minitab to construct a scatter diagram of the data points

A regression analysis between weight (y in pounds)and height (x in inches)resulted in the following least squares line: $\hat{y}$ = 120 + 5x.This implies that if the height is increased by 1 inch,the weight is expected to:

At the 0.05 level of significance,test the null hypothesis that the population coefficient of correlation is really zero. :p=0 :p0

For the values of the coefficient of determination listed below,which one implies the greatest value of SSR (regression sum of squares)given that SST = 500?

What is residual analysis,and what information can it provide?

In a simple linear model,testing whether the slope of the population regression line is zero is the same as testing whether or not the population ____________________ equals zero.

If the standard error of estimate 5_yx = 18 and n = 10, then the error sum of squares, SSE, is:

The vertical spread of the data points about the regression line is measured by the:

For a given value of x,which will be wider,a 90% confidence interval or a 90% prediction interval? Explain

The number of degrees of freedom associated with the standard error of estimate is

Another name for the residual term in a regression equation is:

Briefly describe each of the following: a)Homoscedasticity b)Residual

A Preview of Business Statistics

Visual Description of Data

Statistical Description of Data

Data Collection and Sampling Methods

Probability: Review of Basic Concepts

Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Estimation From Sample Data

Hypothesis Tests Involving a Sample Mean or Proportion

Hypothesis Tests Involving Two Sample Means

Analysis of Variance Tests

Chi-Square Applications

Nonparametric Methods

Multiple Regression and Correlation

Model Building

Models for Time Series and Forecasting

Decision Theory

Total Quality Management

Filters

Exam 15: Simple Linear Regression and Correlation

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

Consider the following data values of variables x and y 4 2 6 4 3 5 3 7 6 5 Use Excel or Minitab to construct a scatter diagram of the data points

A regression analysis between weight (y in pounds)and height (x in inches)resulted in the following least squares line: y^\hat{y}y^​ = 120 + 5x.This implies that if the height is increased by 1 inch,the weight is expected to:

At the 0.05 level of significance,test the null hypothesis that the population coefficient of correlation is really zero. :p=0 :p0

For the values of the coefficient of determination listed below,which one implies the greatest value of SSR (regression sum of squares)given that SST = 500?

What is residual analysis,and what information can it provide?

In a simple linear model,testing whether the slope of the population regression line is zero is the same as testing whether or not the population ____________________ equals zero.

If the standard error of estimate 5yx = 18 and n = 10, then the error sum of squares, SSE, is:

The vertical spread of the data points about the regression line is measured by the:

For a given value of x,which will be wider,a 90% confidence interval or a 90% prediction interval? Explain

The number of degrees of freedom associated with the standard error of estimate is

Another name for the residual term in a regression equation is:

Briefly describe each of the following: a)Homoscedasticity b)Residual

A Preview of Business Statistics

Visual Description of Data

Statistical Description of Data

Data Collection and Sampling Methods

Probability: Review of Basic Concepts

Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Estimation From Sample Data

Hypothesis Tests Involving a Sample Mean or Proportion

Hypothesis Tests Involving Two Sample Means

Analysis of Variance Tests

Chi-Square Applications

Nonparametric Methods

Multiple Regression and Correlation

Model Building

Models for Time Series and Forecasting

Decision Theory

Total Quality Management

Filters

A regression analysis between weight (y in pounds)and height (x in inches)resulted in the following least squares line: $\hat{y}$ = 120 + 5x.This implies that if the height is increased by 1 inch,the weight is expected to:

If the standard error of estimate 5_yx = 18 and n = 10, then the error sum of squares, SSE, is: