(h) Using R-Studio, carry out relevant tests to determine if the assumptions of normality and homogeneity of variance were violated. Carefully discuss your findings quoting relevant statistics in your response and provide the necessary hypotheses. (Provide

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Answer sub part H

A company is trying to determine if the colour of the box has any effect on sales. Three
different coloured boxes are sent to their distributors and a check is made at the end of the
week on the number of sales in each store.
Red
43
52
59
76
61
81
(a) Prepare the analysis of variance table manually (Show ALL workings).
(b) State the null hypothesis(es), the decision rule for a = 0.05 and make the decision
for each hypothesis.
A
B
Yellow
52
37
38
64
74
(c) Confirm your answer using R-Studio. Provide the code used and relevant output
tables.
C
D
(d) Using R-Studio, carry out relevant tests to determine if the assumptions of normality
and homogeneity of variance were violated. Carefully discuss your findings quoting
relevant statistics in your response and provide the necessary hypotheses. (Provide
the code used and relevant output tables.)
The company expanded their analysis to compare the effect on the sale of three box colours
in four different countries. The results are displayed below:
Box Colour
Yellow
Country Red
47
56
Country
A
B
C
D
Blue
61
29
38
53
79
49
41
52
54
63
44
The results for a second store in each company is added to the study. The results are
displayed below:
Box Colour
Red Yellow
45
49
43
38
50
51
60
49
Blue
60
52
55
48
Blue
54
58
50
44
Combine the data from the two sets of trials and
(e) Prepare the analysis of variance table manually (Show ALL workings).
(f) State the null hypothesis(es) in words, the decision rule for a = 0.05 and make the
decision for each hypothesis.
(g) Confirm your answer using R-Studio. Provide the code used and relevant output
tables.
3
(h) Using R-Studio, carry out relevant tests to determine if the assumptions of normality
and homogeneity of variance were violated. Carefully discuss your findings quoting
relevant statistics in your response and provide the necessary hypotheses. (Provide
the code used and relevant output tables.)
Transcribed Image Text:A company is trying to determine if the colour of the box has any effect on sales. Three different coloured boxes are sent to their distributors and a check is made at the end of the week on the number of sales in each store. Red 43 52 59 76 61 81 (a) Prepare the analysis of variance table manually (Show ALL workings). (b) State the null hypothesis(es), the decision rule for a = 0.05 and make the decision for each hypothesis. A B Yellow 52 37 38 64 74 (c) Confirm your answer using R-Studio. Provide the code used and relevant output tables. C D (d) Using R-Studio, carry out relevant tests to determine if the assumptions of normality and homogeneity of variance were violated. Carefully discuss your findings quoting relevant statistics in your response and provide the necessary hypotheses. (Provide the code used and relevant output tables.) The company expanded their analysis to compare the effect on the sale of three box colours in four different countries. The results are displayed below: Box Colour Yellow Country Red 47 56 Country A B C D Blue 61 29 38 53 79 49 41 52 54 63 44 The results for a second store in each company is added to the study. The results are displayed below: Box Colour Red Yellow 45 49 43 38 50 51 60 49 Blue 60 52 55 48 Blue 54 58 50 44 Combine the data from the two sets of trials and (e) Prepare the analysis of variance table manually (Show ALL workings). (f) State the null hypothesis(es) in words, the decision rule for a = 0.05 and make the decision for each hypothesis. (g) Confirm your answer using R-Studio. Provide the code used and relevant output tables. 3 (h) Using R-Studio, carry out relevant tests to determine if the assumptions of normality and homogeneity of variance were violated. Carefully discuss your findings quoting relevant statistics in your response and provide the necessary hypotheses. (Provide the code used and relevant output tables.)
Expert Solution
Step 1

h)

Data for the first store:

Country\Box colour Red Yellow Blue
A 47 52 60
B 56 54 52
C 49 63 55
D 41 44 48

Normality assumption test:

Null Hypothesis:

H0: Normality assumption was not violated

Alternative Hypothesis:

H1: Normality assumption was violated.

R syntax:

Statistics homework question answer, step 1, image 1

From the output, the p value is 0.02882.

 

From the given information, α=0.05.

Decision Rule:

If p-value ≤ α, then reject the null hypothesis.

 

Conclusion:

The level of significance is α=0.05

Here, the p-value is less than the level of significance.

From the decision rule, reject the null hypothesis.

Thus, Normality assumption was violated.

 

Homogeneity of variance test:

Null Hypothesis:

H0: Homogeneity of variance assumption was not violated

Alternative Hypothesis:

H1: Homogeneity of variance assumption was violated.

R syntax:

 

Statistics homework question answer, step 1, image 2

From the output, the p value for color group is 0.7827.

Conclusion:

The level of significance is α=0.05

Here, the p-value is greater than the level of significance.

From the decision rule, failed to reject the null hypothesis.

From the output, the p value for Country group is 0.4351

Here, the p-value is greater than the level of significance.

From the decision rule, failed to reject the null hypothesis.

Hence, the Homogeneity of variance assumption was not violated.

Thus, the normality assumption violated and Homogeneity of variance assumption was not violated for the ANOVA technique of first store data.

 

 

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