Question

1. Listed below are grade average for randomly selected students with three different categories of high-school background.  At the 0.05 level of significance, use the Kruskal-Wallis test the claim that the three groups have the same median grade average.  (note that the data have already been ranked, and the sum of the ranks is shown for each column).

Good	Fair	Poor
3.21	2.87	2.01
3.65	3.05	2.31
1.00	2.00	2.98
3.12	0.00	0.50
2.75	1.98	2.36
R1 = 32	R2 = 34	R3 = 54

Answer 1

H0 : the three groups comes from populations which have the same median grade average.

H1 : the three groups come from the populations which don't have the same median grade average.