
Chapter 18
PB
Non-Parametric Statistics
801
The Kruskal–Wallis statistic (K) can be computed by rst computing the ranks of values given
in Table 18.20.
TABLE 18.21
Ranking of the hours spent on paper work by the employees of different departments
Production Housekeeping HRD Marketing
1.0 9.5 15.0 26.5
4.5 12.5 17.5 24.5
2.5 9.5 19.0 22.5
6.0 14.0 16.0 24.5
7.0 12.5 17.5 28.0
4.5 9.5 20.0 26.5
2.5 9.5 21.0 22.5
T
1
= 28 T
2
= 77 T
3
= 126 T
4
= 175
As discussed in the chapter, the Kruskal–Wallis statistic (K) is de ned as below:
K
nn
T
n
n
j
j
j
k
=
+
⎛
⎝
⎜
⎞
⎠
⎟
=
∑
12
1
2
1
()
where
T
n
j
j
j
k
2
1
22 22
28
7
77
7
126
7
175
7
=
∑
⎛
⎝
⎜
⎞
⎠
⎟
=++
() () () ()
7602
K =
×+
−+=−=
12
28 28 1
7602 3281 112 3448 ...