MYLAB STATISTICS: ELEMENTARY STATISTICS
7th Edition
ISBN: 9780135901021
Author: Larson
Publisher: PEARSON EDUCATION (COLLEGE)
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Chapter 1, Problem 3CQ
Determine whether the study is an observational study or an experiment. Explain.
- (a) Researchers conduct a study to determine whether body mass index (BMI) influences mortality. To conduct the study, researchers obtained the BMIs of 3,951.455 people. (Source: Elsevier Ltd.)
- (b) Researchers conduct a study to determine whether taking a multivitamin daily affects cognitive health among men as they age. To perform the study, researchers studied 5947 male physicians ages 65 years or older and had one group lake a multivitamin daily and had another group take a placebo daily. (Source: American College Physicians)
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