21.01.2022 Views

Statistics for the Behavioral Sciences by Frederick J. Gravetter, Larry B. Wallnau ISBN 10: 1305504917 ISBN 13: 9781305504912

Statistics is one of the most practical and essential courses that you will take, and a primary goal of this popular text is to make the task of learning statistics as simple as possible. Straightforward instruction, built-in learning aids, and real-world examples have made STATISTICS FOR THE BEHAVIORAL SCIENCES, 10th Edition the text selected most often by instructors for their students in the behavioral and social sciences. The authors provide a conceptual context that makes it easier to learn formulas and procedures, explaining why procedures were developed and when they should be used. This text will also instill the basic principles of objectivity and logic that are essential for science and valuable in everyday life, making it a useful reference long after you complete the course.

Statistics is one of the most practical and essential courses that you will take, and a primary goal of this popular text is to make the task of learning statistics as simple as possible. Straightforward instruction, built-in learning aids, and real-world examples have made STATISTICS FOR THE BEHAVIORAL SCIENCES, 10th Edition the text selected most often by instructors for their students in the behavioral and social sciences. The authors provide a conceptual context that makes it easier to learn formulas and procedures, explaining why procedures were developed and when they should be used. This text will also instill the basic principles of objectivity and logic that are essential for science and valuable in everyday life, making it a useful reference long after you complete the course.

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

APPENDIX C | Solutions for Odd-Numbered Problems in the Text 679

CHAPTER 16

Introduction To Regression

1. Figure C4

Y

7 Y 5 2X 2 1

6

5

4

Y 5 2X 1 8

3

2

1

X

6543210

7

3. a. r = 0.25

b. Ŷ = 0.5X + 6

5. The standard error of estimate is a measure of the

average distance between the predicted Y points from

the regression equation and the actual Y points in

the data.

7. SS X

= 16, SS Y

= 134, SP = 32. With M X

= 4 and

M Y

= 6, the regression equation is Ŷ = 2X − 2.

9. SS regression

= r 2 SS Y

= 39.95 with df = 1. MS residual

=

10.05

4

39.95

= 2.51. F = 2.51 = 15.92. With df = 1, 4, the

F-ratio is significant with Ŷ = .05.

11. a. SS weight

= 18,SS income

= 21,609, SP = 330.

Ŷ = 18.33X + 33

b. r = −0.529 and r 2 = 0.280

c. F = 2.33 with df = 1, 6. The regression

equation is not significant.

13. a. Ŷ = 1.38X + 7.34

b. r 2 = 0.743 or 74.3%

c. F = 20.23 with df = 1, 7. The equation accounts

for a significant portion of the variance.

15. a. The standard error of estimate is Ï 36

16 = 1.50.

b. The standard error of estimate is

Ï 36

64 = 0.75.

17. a. df = 1, 18

b. n = 25 pairs of scores

19. a. F = 7.6

1.46 = 5.21. With df = 2, 17, the critical value

is 3.59. The equation does account for a significant

portion of the variance.

b. F = 7.6

3.54 = 2.15. With df = 2, 7, the equation is

not significant.

21. a. SS crime

= 230, SS prevention

= 230, SS population

= 8, and.

SP for crime and prevention is 40, SP for crime

and population is 40, and SP for prevention and

population is 176, and. The regression equation is

Ŷ = −0.8X 1

19X 2

, where X 1

is the amount spent

on prevention and X 2

is the population.

b. R 2 = 0.953 or 93.5%

23. Ŷ = 1.242X 1

− 0.048X 2

+ 0.565

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!