A linear regression, statistics homework help

/in /by

A linear regression, statistics homework help

Question 1 of 20

A linear regression

 A. gives a relationship between two variables that can be described by a line.  

 B. gives a relationship between two variables that cannot be described by a line.  

 C. gives a relationship between three variables that can be described by a line.  

 D. contains only two variables.

Question 2 of 20

In a regression model, the slope represents the

 A.  point where the y-axis intersects the x-axis.  

 B.  change in y due to a one unit change in x.  

 C.  point where the x-axis intersects the y-axis.  

 D.  change in the independent variable due to a one unit change in the dependent variable.

Question 3 of 20

In the equation y = 12 + 6x, 12 is the

 A.  independent variable  

 B.  slope of the line.  

 C.  dependent variable  

 D.  y-intercept.  

Question 4 of 20

In the equation y = 100 – 5x  , 100 is the

 A.  value of y when x is equal to 1.  

 B.  point where the line intersects the x-axis.  

 C.  change in y due to a one-unit change in x.  

 D.  point where the line intersects the y-axis.  

Question 5 of 20

In the equation y = 100 – 5x, −5 is the

 A.  value of y when x is equal to 1.  

 B.  point where the line intersects the x-axis.  

 C.  change in y due to a one-unit change in x.  

 D.  change in x due to a one-unit change in y.  

Question 6 of 20

In the regression model y = A + Bx + e, x is the

 A.  dependent variable  

 B.  independent variable.  

 C.  error term  

 D.  missing variable.  

Question 7 of 20

In the regression model ŷ = a = bx, a and b are the

 A.  estimates of the population parameters, A and B.  

 B.  random variables.  

 C.  population parameters.  

 D.  omitted variables.  

Question 8 of 20

For a data set on x and y, the value of SSxx is 773, SSxy is 1297, the mean of the x values is 89, and the mean of the y values is 19. What is the value of a in the regression of y on x?

 A.  57.12  

 B.  168.33  

 C.  −34.04  

 D.  −130.33  

Question 9 of 20

The table shown below gives six pairs of x and y values.

X

Y

16

8

20

13

12

9

10

5

14

6

9

4

What are the values of SSxx and SSxy ?

 A.  SSXX = 58.5, SSxy = 83.500

 B.  SSXX = 24.138, SSxy = 22.819

 C.  SSXX = 83.5, SSxy = 58.500 

 D.  SSXX = 22.819, SSxy = 24.138

Question 10 of 20

The following table lists the monthly incomes (in hundreds of dollars) and the monthly rents paid (in hundreds of dollars) by a sample of six families.  

Monthly Income

Monthly Rent

24

7

16

4.5

19

6.5

31

12.8

11

4.5

27

8.5

For the regression of y on x, what are the values of a and b?

 A.  a = .384, b = −.89  

 B.  a = −3.75, b = .52  

 C.  a = .52, b = −3.75  

 D.  a = −.89, b = .384  

Question 11 of 20

The following table lists the number of years of use and the prices (in thousands of dollars) by a sample of six houses.

Years

Price

27

165

15

182

3

205

35

187

9

180

18

161

Suppose we have information on the years of use and the prices of a sample of houses. In the regression of price on the number of years of use, the value of b will represent

 A.  the point where this regression line will intersect the y-axis.  

 B.  the point where this regression line will intersect the x-axis.  

 C.  a decrease in the number of years of use of a house due to a $1000 increase in its price.  

 D.  a decrease in the price of a house due to a one year increase in its use.  

Question 12 of 20

A perfect positive correlation means

 A.  the points in a scatter diagram lie on an upward sloping line.  

 B.  the points in a scatter diagram lie on a downward sloping line.  

 C.  r is equal to −1.  

 D.  r is equal to 0.  

Question 13 of 20

The value of the correlation coefficient is zero if the points in a scatter diagram

 A.  lie on an upward sloping line.  

 B.  lie on a downward sloping line.  

 C.  are scattered all over the diagram.  

 D.  are close to the regression line.  

Question 14 of 20

In the regression model ŷ = a + bx, ŷ is the

 A.  actual value of y.  

 B.  predicted value of y.  

 C.  value of y when a and b are zero.  

 D.  missing value of y.  

Question 15 of 20

We construct a scatter diagram by

 A.  scattering the values of x over the values of y.  

 B.  scattering the values of y over the values of x.  

 C.  plotting the paired values of x and y.  

 D.  plotting the values of A and B.  

Question 16 of 20

The value of y obtained for an element from a survey is the

 A.  predicted value of y  

 B.  estimated value of y .  

 C.  actual value of y  

 D.  residual.  

Question 17 of 20

The least squares method minimizes the

 A.  difference between the y and x values.  

 B.  sum of the errors.  

 C.  sum of the squares of errors.  

 D.  sum of the y values.  

Question 18 of 20

The table shown below gives seven pairs of x and y values.

X

Y

12

18

9

35

14

12

8

40

10

23

3

33

18

10

Using the regression of y on x, what is the predicted value of y for x = 9?

 A.  24.43  

 B.  −4.13  

 C.  27.67  

 D.  22.21  

Question 19 of 20

A simple regression model contains

 A.  two independent variables.  

 B.  two dependent variables.  

 C.  one independent and one dependent variable.  

 D.  more than one independent variable.  

Question 20 of 20

In the regression model y = A + Bx + e  , e is the

 A.  slope of the regression line

 B.  random error term.

 C.  y-intercept

 D.  missing variable.