People in the United States spend a lot of money for the pur

People in the United States spend a lot of money for the purchase of magnets to treat a variety of pains (currently around $5 billion annually). Researchers conducted a study to determine whether magnets are effective in treating back pain. Pain was measured using a number scale. People were randomly assigned to either the magnet treatment or a placebo treatment. For each person the reduction in the amount of pain during the study was measured. Did magnets reduce back pain for people? Data do not meet assumptions of parametric test. Which nonparametric test do you use?

1 population sign test

2 population sign test

Spearmen\'s Rank test

Mann Whitney U Test

Dr. Spock want to know if a new drug called Omega significantly decreases the time it takes rats to move through a maze. He has a colony of 100 genetically identical mice. Half are randomly assigned to Omega and half are assigned to a placebo. Test whether the drug decreases the time rats are in the maze.  

Data do not meet assumptions of normality, which nonparametric test do you use?

Mean time rats given the placebo: 40 seconds with a standard deviation of 2.

What statistical test will you use?

1 population sign test

2 population sign test

Spearmen\'s Rank test

Mann Whitney U Test

Solution

(1) Answer: Mann Whitney U Test

It is a two-unpaired groups. So we use Mann Whitney U Test.

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(2) Answer: Mann Whitney U Test

It is a two-unpaired groups. So we use Mann Whitney U Test.