Intro Stats
4th Edition
ISBN: 9780321826275
Author: Richard D. De Veaux
Publisher: PEARSON
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Chapter 11, Problem 61E
Skydiving, anyone? A humor piece published in the British Medical Journal (“Parachute use to prevent death and major trauma related to gravitational challenge: Systematic review of randomized control trials,” Gordon, Smith, and Pell, BMJ, 2003:327) notes that we can’t tell for sure whether parachutes are safe and effective because there has never been a properly randomized, double-blind, placebo-controlled study of parachute effectiveness in skydiving. (Yes, this is the sort of thing statisticians find funny… .) Suppose you were designing such a study.
- a) What is the factor in this experiment?
- b) What experimental units would you propose?11
- c) What would serve as a placebo for this study?
- d) What would the treatments be?
- e) What would the response variable be?
- f) What sources of variability would you control?
- g) How would you randomize this “experiment”?
- h) How would you make the experiment double-blind?
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Intro Stats
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