82
Bluman, Chapter 11 Chapter 11 Other Chi-Square Tests 1 1 Friday, January 25, 13

Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

  • Upload
    others

  • View
    24

  • Download
    1

Embed Size (px)

Citation preview

Page 1: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11

Other Chi-Square Tests

1

1Friday, January 25, 13

Page 2: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11 Overview Introduction 11-1 Test for Goodness of Fit 11-2 Tests Using Contingency Tables

2

2Friday, January 25, 13

Page 3: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11 Objectives1. Test a distribution for goodness of fit, using chi-

square.2. Test two variables for independence, using chi-

square.3. Test proportions for homogeneity, using chi-

square.

3

3Friday, January 25, 13

Page 4: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

11.1 Test for Goodness of Fit The chi-square statistic can be used to

see whether a frequency distribution fits a specific pattern. This is referred to as the chi-square goodness-of-fit test.

4

4Friday, January 25, 13

Page 5: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Test for Goodness of Fit

Formula for the test for goodness of fit:

5

5Friday, January 25, 13

Page 6: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Assumptions for Goodness of Fit1. The data are obtained from a random sample.

2. The expected frequency for each category must be 5 or more.

6

6Friday, January 25, 13

Page 7: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11Other Chi-Square Tests

Section 11-1Example 11-1Page #592

7

7Friday, January 25, 13

Page 8: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

8Friday, January 25, 13

Page 9: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

8Friday, January 25, 13

Page 10: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

8Friday, January 25, 13

Page 11: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

8Friday, January 25, 13

Page 12: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 1: State the hypotheses and identify the claim.

8Friday, January 25, 13

Page 13: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 1: State the hypotheses and identify the claim.H0: Consumers show no preference (claim).

8Friday, January 25, 13

Page 14: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda FlavorsA market analyst wished to see whether consumers have any preference among five flavors of a new fruit soda. A sample of 100 people provided the following data. Is there enough evidence to reject the claim that there is no preference in the selection of fruit soda flavors, using the data shown previously? Let α = 0.05.

8

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 1: State the hypotheses and identify the claim.H0: Consumers show no preference (claim).H1: Consumers show a preference.

8Friday, January 25, 13

Page 15: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

9Friday, January 25, 13

Page 16: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value.

9Friday, January 25, 13

Page 17: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value. D.f. = 5 – 1 = 4, and α = 0.05. CV = 9.488.

9Friday, January 25, 13

Page 18: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value. D.f. = 5 – 1 = 4, and α = 0.05. CV = 9.488.

Step 3: Compute the test value.

9Friday, January 25, 13

Page 19: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value. D.f. = 5 – 1 = 4, and α = 0.05. CV = 9.488.

Step 3: Compute the test value.

9Friday, January 25, 13

Page 20: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value. D.f. = 5 – 1 = 4, and α = 0.05. CV = 9.488.

Step 3: Compute the test value.

9Friday, January 25, 13

Page 21: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-1: Fruit Soda Flavors

9

Cherry Strawberry Orange Lime GrapeObserved 32 28 16 14 10Expected 20 20 20 20 20

Step 2: Find the critical value. D.f. = 5 – 1 = 4, and α = 0.05. CV = 9.488.

Step 3: Compute the test value.

9Friday, January 25, 13

Page 22: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Step 5: Summarize the results.There is enough evidence to reject the claim that consumers show no preference for the flavors.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 23: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Step 5: Summarize the results.There is enough evidence to reject the claim that consumers show no preference for the flavors.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 24: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 25: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 26: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 27: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 28: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 29: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Step 5: Summarize the results.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 30: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.The decision is to reject the null hypothesis, since 18.0 > 9.488.

Step 5: Summarize the results.There is enough evidence to reject the claim that consumers show no preference for the flavors.

Example 11-1: Fruit Soda Flavors

10

10Friday, January 25, 13

Page 31: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11Other Chi-Square Tests

Section 11-1Example 11-2Page #594

11

11Friday, January 25, 13

Page 32: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: RetireesThe Russel Reynold Association surveyed retired senior executives who had returned to work. They found that after returning to work, 38% were employed by another organization, 32% were self-employed, 23% were either freelancing or consulting, and 7% had formed their own companies. To see if these percentages are consistent with those of Allegheny County residents, a local researcher surveyed 300 retired executives who had returned to work and found that 122 were working for another company, 85 were self-employed, 76 were either freelancing or consulting, and 17 had formed their own companies. At α = 0.10, test the claim that the percentages are the same for those people in Allegheny County.

12

12Friday, January 25, 13

Page 33: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: RetireesThe Russel Reynold Association surveyed retired senior executives who had returned to work. They found that after returning to work, 38% were employed by another organization, 32% were self-employed, 23% were either freelancing or consulting, and 7% had formed their own companies. To see if these percentages are consistent with those of Allegheny County residents, a local researcher surveyed 300 retired executives who had returned to work and found that 122 were working for another company, 85 were self-employed, 76 were either freelancing or consulting, and 17 had formed their own companies. At α = 0.10, test the claim that the percentages are the same for those people in Allegheny County.

12

12Friday, January 25, 13

Page 34: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 35: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 36: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 37: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 38: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 39: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

13Friday, January 25, 13

Page 40: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 1: State the hypotheses and identify the claim.

13Friday, January 25, 13

Page 41: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 1: State the hypotheses and identify the claim.H0: The retired executives who returned to work

are distributed as follows: 38% are employed by another organization, 32% are self-employed, 23% are either freelancing or consulting, and 7% have formed their own companies (claim).

13Friday, January 25, 13

Page 42: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

13

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 1: State the hypotheses and identify the claim.H0: The retired executives who returned to work

are distributed as follows: 38% are employed by another organization, 32% are self-employed, 23% are either freelancing or consulting, and 7% have formed their own companies (claim).

H1: The distribution is not the same as stated in the null hypothesis.

13Friday, January 25, 13

Page 43: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

14

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 2: Find the critical value.

14Friday, January 25, 13

Page 44: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

14

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 2: Find the critical value. D.f. = 4 – 1 = 3, and α = 0.10. CV = 6.251.

Step 3: Compute the test value.

14Friday, January 25, 13

Page 45: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

14

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 2: Find the critical value. D.f. = 4 – 1 = 3, and α = 0.10. CV = 6.251.

Step 3: Compute the test value.

14Friday, January 25, 13

Page 46: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

14

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 2: Find the critical value. D.f. = 4 – 1 = 3, and α = 0.10. CV = 6.251.

Step 3: Compute the test value.

14Friday, January 25, 13

Page 47: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-2: Retirees

14

New Company Self-Employed

Free-lancing

Owns Company

Observed 122 85 76 17

Expected .38(300)=114

.32(300)=96

.23(300)=69

.07(300)=21

Step 2: Find the critical value. D.f. = 4 – 1 = 3, and α = 0.10. CV = 6.251.

Step 3: Compute the test value.

14Friday, January 25, 13

Page 48: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Step 5: Summarize the results.There is not enough evidence to reject the claim. It can be concluded that the percentages are not significantly different from those given in the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 49: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Step 5: Summarize the results.There is not enough evidence to reject the claim. It can be concluded that the percentages are not significantly different from those given in the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 50: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 51: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 52: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 53: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 54: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 55: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Step 5: Summarize the results.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 56: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Since 3.2939 < 6.251, the decision is not to reject the null hypothesis.

Step 5: Summarize the results.There is not enough evidence to reject the claim. It can be concluded that the percentages are not significantly different from those given in the null hypothesis.

Example 11-2: Retirees

15

15Friday, January 25, 13

Page 57: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Chapter 11Other Chi-Square Tests

Section 11-1Example 11-3Page #595

16

16Friday, January 25, 13

Page 58: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm DeathsA researcher read that firearm-related deaths for people aged 1 to 18 were distributed as follows: 74% were accidental, 16% were homicides, and 10% were suicides. In her district, there were 68 accidental deaths, 27 homicides, and 5 suicides during the past year. At α = 0.10, test the claim that the percentages are equal.

17

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

17Friday, January 25, 13

Page 59: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm DeathsA researcher read that firearm-related deaths for people aged 1 to 18 were distributed as follows: 74% were accidental, 16% were homicides, and 10% were suicides. In her district, there were 68 accidental deaths, 27 homicides, and 5 suicides during the past year. At α = 0.10, test the claim that the percentages are equal.

17

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

17Friday, January 25, 13

Page 60: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm DeathsA researcher read that firearm-related deaths for people aged 1 to 18 were distributed as follows: 74% were accidental, 16% were homicides, and 10% were suicides. In her district, there were 68 accidental deaths, 27 homicides, and 5 suicides during the past year. At α = 0.10, test the claim that the percentages are equal.

17

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

17Friday, January 25, 13

Page 61: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm DeathsA researcher read that firearm-related deaths for people aged 1 to 18 were distributed as follows: 74% were accidental, 16% were homicides, and 10% were suicides. In her district, there were 68 accidental deaths, 27 homicides, and 5 suicides during the past year. At α = 0.10, test the claim that the percentages are equal.

17

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

17Friday, January 25, 13

Page 62: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

Step 1: State the hypotheses and identify the claim.

18

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

18Friday, January 25, 13

Page 63: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

Step 1: State the hypotheses and identify the claim.H0: Deaths due to firearms for people aged 1

through 18 are distributed as follows: 74% accidental, 16% homicides, and 10% suicides (claim).

18

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

18Friday, January 25, 13

Page 64: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

Step 1: State the hypotheses and identify the claim.H0: Deaths due to firearms for people aged 1

through 18 are distributed as follows: 74% accidental, 16% homicides, and 10% suicides (claim).

H1: The distribution is not the same as stated in the null hypothesis.

18

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

18Friday, January 25, 13

Page 65: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

19

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

Step 2: Find the critical value.

19Friday, January 25, 13

Page 66: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

19

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

Step 2: Find the critical value. D.f. = 3 – 1 = 2, and α = 0.10. CV = 4.605.

Step 3: Compute the test value.

19Friday, January 25, 13

Page 67: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

19

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

Step 2: Find the critical value. D.f. = 3 – 1 = 2, and α = 0.10. CV = 4.605.

Step 3: Compute the test value.

19Friday, January 25, 13

Page 68: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

19

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

Step 2: Find the critical value. D.f. = 3 – 1 = 2, and α = 0.10. CV = 4.605.

Step 3: Compute the test value.

19Friday, January 25, 13

Page 69: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Example 11-3: Firearm Deaths

19

Accidental Homicides SuicidesObserved 68 27 5Expected 74 16 10

Step 2: Find the critical value. D.f. = 3 – 1 = 2, and α = 0.10. CV = 4.605.

Step 3: Compute the test value.

19Friday, January 25, 13

Page 70: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Step 5: Summarize the results.There is enough evidence to reject the claim that the distribution is 74% accidental, 16% homicides, and 10% suicides.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 71: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Step 5: Summarize the results.There is enough evidence to reject the claim that the distribution is 74% accidental, 16% homicides, and 10% suicides.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 72: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 73: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 74: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 75: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 76: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 77: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 78: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Step 5: Summarize the results.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 79: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Step 4: Make the decision.Reject the null hypothesis, since 10.549 > 4.605.

Step 5: Summarize the results.There is enough evidence to reject the claim that the distribution is 74% accidental, 16% homicides, and 10% suicides.

Example 11-3: Firearm Deaths

20

20Friday, January 25, 13

Page 80: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Test for Normality (Optional) The chi-square goodness-of-fit test can be used

to test a variable to see if it is normally distributed.

21

21Friday, January 25, 13

Page 81: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Test for Normality (Optional) The chi-square goodness-of-fit test can be used

to test a variable to see if it is normally distributed.

The hypotheses are:H0: The variable is normally distributed.H1: The variable is not normally distributed.

21

21Friday, January 25, 13

Page 82: Chapter 11 - navimath...2013/01/25  · Bluman, Chapter 11 Chapter 11 Objectives 1. Test a distribution for goodness of fit, using chi-square. 2. Test two variables for independence,

Bluman, Chapter 11

Test for Normality (Optional) The chi-square goodness-of-fit test can be used

to test a variable to see if it is normally distributed.

The hypotheses are:H0: The variable is normally distributed.H1: The variable is not normally distributed.

This procedure is somewhat complicated. The calculations are shown in example 11-4 on page 597 in the text.

21

21Friday, January 25, 13