##### Question

In: Statistics and Probability

# 1. Nine students took the SAT test. Their scores are listed below. Later on, they took...

1. Nine students took the SAT test. Their scores are listed below. Later on, they took a test preparation course and retook the SAT. Their new scores are listed below. Use the Sign test to test the claim that the test preparation has no effect on their scores. Use α = 0.05.

 Student 1 2 3 4 5 6 7 8 9 Before 860 820 910 990 1000 930 870 1180 920 After 880 820 900 1030 1030 940 860 1220 940

2. A medical researcher wishes to try three different techniques to lower blood pressure of patients with high blood pressure. The subjects are randomly selected and randomly assigned to one of three groups. Group 1 is given medication, Group 2 is given an exercise program, and Group 3 is assigned a special diet. At the end of six weeks, the reduction in each subject's blood pressure is recorded. Use the Kruskal-Wallis test to test the claim that there is no difference in the distributions of the blood pressures of the three populations. Use α = 0.05.

 Group 1 Group 2 Group 3 13 14 11 17 15 10 10 7 4 5 6 2 8 14 6 10 11 6

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