1. Copyright © 2012 Pearson Education, Inc. All rights reserved. Chapter 8 Residual Analysis

2. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.1 Introduction

3. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.2 Regression Residuals

4. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 4 Figure 8.1 Actual random error  and regression residual  ^

5. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 5

6. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 6

7. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 7 Figure 8.2 SAS printout for first- order model continued on next slide

8. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 8 Figure 8.2 SAS printout for first- order model (cont’d)

9. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 9 Figure 8.3 SAS printout for quadratic (second-order) model continued on next slide

10. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 10 Figure 8.3 SAS printout for quadratic (second-order) model (cont’d)

11. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.3 Detecting Lack of Fit

12. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 12 Figure 8.4 SAS plot of residuals for the first-order model

13. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 13 Figure 8.5 MINITAB plot of cholesterol data with least squares line

14. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 14 Figure 8.6 SAS plot of residuals for the quadratic model

15. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 15

16. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 16 Figure 8.7 SPSS regression printout for demand model

17. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 17 Figure 8.8 SPSS plot of residuals against price for demand model

18. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 18 Figure 8.9 SPSS partial residual plot for price

19. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 19 Figure 8.10 SPSS regression printout for demand model with transformed price

20. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.4 Detecting Unequal Variances

21. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 21 Figure 8.11 A plot of residuals for poisson data

22. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 22 Figure 8.12 A plot of residuals for binomial data (proportions or percentages)

23. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 23 Figure 8.13 A plot of residuals for data subject to multiplicative errors

24. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 24

25. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 25

26. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 26 Figure 8.14 MINITAB regression printout for second-order model of salary

27. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 27 Figure 8.15 MINITAB residual plot for second-order model of salary

28. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 28 Figure 8.16 MINITAB regression printout for second-order model of natural log of salary

29. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 29 Figure 8.17 MINITAB residual plot for second-order model of natural log of salary

30. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 30 Figure 8.18 MINITAB regression printout first-order model of natural log of salary

31. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 31 Figure 8.19a SAS regression printout for second-order model of salary: Subsample 1 (years of experience < 20)

32. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 32 Figure 8.19b SAS regression printout for second-order model of salary: Subsample 2 (years of experience > 20)

33. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.5 Checking the Normality Assumption

34. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 34 Figure 8.20 MINITAB histogram of residuals from log model of salary

35. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 35 Figure 8.21 MINITAB stem-and-leaf plot of residuals from log model of salary

36. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 36 Figure 8.22 MINITAB normal probability plot of residuals from log model of salary

37. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.6 Detecting Outliners and Identifying Influential Observations

38. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 38

39. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 39 Figure 8.23 MINITAB regression printout for model of fast-food sales continued on next slide

40. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 40 Figure 8.23 MINITAB regression printout for model of fast-food sales (cont’d)

41. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 41 Figure 8.24 MINITAB plot of residuals versus traffic flow

42. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 42 Figure 8.25 MINITAB plot of residuals versus city

43. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 43 Figure 8.26 MINITAB regression printout for model of fast-food sales with corrected data point continued on next slide

44. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 44 Figure 8.26 MINITAB regression printout for model of fast-food sales with corrected data point (cont’d)

45. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 45 Figure 8.27 MINITAB plot of residuals versus traffic flow for model with corrected data point

46. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 46 Figure 8.28 MINITAB plot of residuals versus city for model with corrected data point

47. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 47

48. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 48 Figure 8.29 SAS regression analysis with influence diagnosis for fast-food sales model continued on next slide

49. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 49 Figure 8.29 SAS regression analysis with influence diagnosis for fast-food sales model (cont’d) continued on next slide

50. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 50 Figure 8.29 SAS regression analysis with influence diagnosis for fast-food sales model (cont’d)

51. Copyright © 2012 Pearson Education, Inc. All rights reserved. Section 8.7 Detecting Residual Correlation: The Durbin- Watson test

52. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 52

53. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 53 Figure 8.30 SAS regression printout for model of annual sales

54. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 54 Figure 8.31 SAS plot of residuals for model of annual sales

55. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 55

56. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 56 Figure 8.32 Rejection region for the Durbin-Watson d-test: scale example

57. Copyright © 2012 Pearson Education, Inc. All rights reserved. 8- 57