Question

A sample of 15 consumers provided the following product ratings for three different products. Five consumers were randomly assigned to test and rate each product.

Product
A	B	C
58	88	68
61	97	47
77	96	38
46	89	56
67	98	59

Use the Kruskal-Wallis test and α = 0.05 to determine whether there is a significant difference among the ratings for the products.

a) Find the value of the test statistic.

b) Find the p-value. (Round your answer to three decimal places.)

p-value =

State your conclusion.

Answer 1

Type	score	Rank
A	58	5
A	61	7
A	77	10
A	46	2
A	67	8
B	88	11
B	97	14
B	96	13
B	89	12
B	98	15
C	68	9
C	47	3
C	38	1
C	56	4
C	59	6

	sample size ni		sum of ranks ∑Ri		(∑Ri)2/ni
A	5		32		204.80
B	5		65		845.00
C	5		23		105.80
total N =	15		total =	∑(∑Ri)2/ni =	1155.60
test stast:H=			=(12/(N*(N+1)))*∑(∑Ri)2/ni )-3*(N+1)=		9.780

a)

value of the test statistic =9.78

b)

p value =0.008

reject null hypothesis since p value <0.05