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*Please use excel when anwsering. We don\'t use formulas, just excel. The truste

ID: 3300846 • Letter: #

Question

*Please use excel when anwsering. We don't use formulas, just excel.

The trustee of a firm's pension plan has solicited the opinions of a sample of the firm's employees about a proposed revision of the plan. Is there sufficient evidence at the 5% level to infer that the responses differ among the three groups of employees?

Actual Responses Responses Blue-collar workers White-collar workers Managers For 58 31 13 Against 72 19 7 Expected Responses Responses Blue-collar workers White-collar workers Managers For Against p =

Explanation / Answer

Solution:

Here, we have to use chi square test to check the hypothesis or claim whether there is sufficient evidence that the responses differ among the three groups of employees or not. The null and alternative hypothesis for this test is given as below:

Null hypothesis: H0: There is sufficient evidence to infer that responses differ among three groups of employees.

Alternative hypothesis: Ha: There is insufficient evidence to infer that responses differ among three groups of employees.

The level of significance or alpha value is given as 0.05 or 5%.

The test statistic formula is given as below:

Chi square = [(O – E)^2/E]

Where, O is observed or actual responses and E is expected responses.

E is calculated as below:

E = (Row total * Column total)/Grand total

Calculations for this test are summarises as below:

Actual Responses (O)

Responses

Blue-collar workers

White-collar workers

Managers

Total

For

58

31

13

102

Against

72

19

7

98

Total

130

50

20

200

Expected Responses (E)

Responses

Blue-collar workers

White-collar workers

Managers

Total

For

66.3

25.5

10.2

102

Against

63.7

24.5

9.8

98

Total

130

50

20

200

p =

0.04711951

O

E

(O - E)

(O - E)^2

(O - E)^2/E

58

66.3

-8.3

68.89

1.039064857

72

63.7

8.3

68.89

1.081475667

31

25.5

5.5

30.25

1.18627451

19

24.5

-5.5

30.25

1.234693878

13

10.2

2.8

7.84

0.768627451

7

9.8

-2.8

7.84

0.8

Chi square test statistic

6.110136362

P-value

0.047119508

P-value is less than the given level of significance or alpha value 0.05, so we reject the null hypothesis that there is sufficient evidence to infer that responses differ among three groups of employees.

There is insufficient evidence to conclude that responses differ among three groups of employees.

Actual Responses (O)

Responses

Blue-collar workers

White-collar workers

Managers

Total

For

58

31

13

102

Against

72

19

7

98

Total

130

50

20

200

Expected Responses (E)

Responses

Blue-collar workers

White-collar workers

Managers

Total

For

66.3

25.5

10.2

102

Against

63.7

24.5

9.8

98

Total

130

50

20

200

p =

0.04711951