# Biostatistics homework

*label*Statistics

*timer*Asked: Dec 7th, 2015

**Question description**

1. An investigator wants to test if there is a difference in endotoxin levels in children who are exposed to endotoxin as a function of their proximity to operating farms. The following are endotoxin levels in units per milligram of dust sampled from children’s mattresses, organized by children’s proximity to farms.

Within 5 Miles 54 62 78 90 70

5-24.9 Miles 28 42 39 81 65

25-49.9 Miles 37 29 30 50 53

50 Miles or More 36 19 22 28 27

Total Sample (Ordered Smallest to Largest) |
|||||||

< 5 Miles |
5-24.9 Miles |
25-49.9 Miles |
50+ Miles |
< 5 Miles |
5-24.9 Miles |
25-49.9 Miles |
50+ Miles |

Apply the Kruskal Wallis test at a 5% level of significance.

Alpha= ________

df= ________

Critical value= ________

H= ________

Based on comparing H to the critical value to the Critical value which of the following is (are) true?

A. There __is __significant evidence at
alpha=0.05 t o show that the populations of endotoxin levels in children living varying distances from operating farms are
not equal.

B. There __is not__ significant evidence at alpha
=0.05 to show that the populations of endotoxin levels in children living varying distances from operating farms are
not equal.

C. There are not enough data points to reach a conclusion.

D. The tied value makes the analysis suspect.