James Madison University Statistics Worksheet

You suspect that either one, or both of your competitors have infringed a product for which you hold a patent. You take samples from each of your competitors “B” and “C” and compare them to a sample of your product “A” using a Kruskal-Wallis Test at 95%.

Your null hypothesis is that all three samples come from the same population

A B C

36 49 71

48 33 31

5 60 140

67 2 59

53 55 42

The Test Stat “H” and crital values are closest to

Select one:

a.

Test Stat = 6.44 Critical Value = 7.378 Cannot Reject

b.

Test Stat = 6.44 Critical Value = 5.991 Cannot Reject

c.

Test Stat = 1.22 Critival Value = 7.738 Cannot Reject

d.

Test Stat = 1.22 Critical Value = 5.991 Cannot Reject

In an experiment to test the toxicity of three chemicals “A”, “B” and “C”, volunteers have each chemical applied to their skin. The degree of irritation is scored from 1 to 10 (10 being the highest). Use a Friedman test at the 99% level of confidence that each chemical comes from the same (but undefined) distribution.

A B C

6 5 3

9 8 4

6 9 3

5 8 6

7 8 9

5 7 6

6 7 5

6 5 7

The Test Statistic “F” and Critical Value are closest to

Select one:

a.

Test Stat = 3.34 Critical Value = 9.210 Cannot Reject

b.

Test Stat = 1.75 Critical Value = 10.597 Cannot Reject

c.

Test Stat = 3.34 Critical Value = 10.597 Cannot Reject

d.

Test Stat = 1.75 Critival Value = 9.210 Cannot Reject