Bundle: Cengage Advantage Books: Essentials of Statistics for the Behavioral Sciences, 8th + Aplia, 1 term Printed Access Card
8th Edition
ISBN: 9781285481685
Author: Frederick J Gravetter, Larry B. Wallnau
Publisher: Cengage Learning
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Chapter 1, Problem 9P
Two researchers are both interested in determining whether large doses of vitamin C can help prevent the common cold. Each obtains a sample of n = 20 college students.
- a. The first researcher interviews each student to determine whether they routinely take a vitamin C supplement. The researcher then records the number of colds each individual gets during the winter. Is this an experimental or a nonexperimental study? Explain your answer.
- b. The second researcher separates the students into two roughly equivalent groups. The students in one group are given a daily multivitamin containing a large amount of vitamin C, and the other group gets a multivitamin with no vitamin C. The researcher then records the number of colds each individual gets during the winter. Is this an experimental or a nonexperimental study? Explain your answer.
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Chapter 1 Solutions
Bundle: Cengage Advantage Books: Essentials of Statistics for the Behavioral Sciences, 8th + Aplia, 1 term Printed Access Card
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