Question

The quality of four brands of soft drinks (SD) are assessed by assigning scores to them.

SD1	SD2	SD3	SD4
8	7	6	5
8	8	6	5
9	5	7	9
9	10	7	6
7	8	12	11

Levene Statistic	df1	df2	Sig.
1.948	3	16	.163

	Shapiro-Wilk
	Statistic	df	Sig.
SD1	.881	5	.314
SD2	.963	5	.826
SD3	.710	5	.012
SD4	.852	5	.201

          

             Test whether there is a difference in the quality between the four brands.

Answer 1

The hypothesis being tested is:

H₀: µ₁ = µ₂ = µ₃ = µ₄

H_a: At least one means is not equal

The output is:

	Mean	n	Std. Dev
	8.2	5	0.84	SD1
	7.6	5	1.82	SD2
	7.6	5	2.51	SD3
	7.2	5	2.68	SD4
	7.7	20	1.95	Total
ANOVA table
Source	SS	df	MS	F	p-value
Treatment	2.55	3	0.850	0.19	.8987
Error	70.00	16	4.375
Total	72.55	19

The p-value from the output is 0.8987.

Since the p-value (0.8987) is greater than the significance level (0.05), we cannot reject the null hypothesis.

Therefore, we cannot conclude that there is a difference in the quality between the four brands.