Introduction to Statistics and Data Analysis
5th Edition
ISBN: 9781305750999
Author: Peck Olson Devore
Publisher: CENGAGE C
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Chapter 1.3, Problem 11E
In a study of whether taking a garlic supplement reduces the risk of getting a cold, participants were assigned to either a garlic supplement group or to a group that did not take a garlic supplement (“Garlic for the Common Cold,” Cochrane Database of Systematic Reviews, 2009). Based on the study, it was concluded that the proportion of people taking a garlic supplement who get a cold is lower than the proportion of those not taking a garlic supplement who get a cold.
- a. What were the researchers trying to learn? What questions motivated their research?
- b. Do you think that the study was conducted in a reasonable way? What additional information would you want in order to evaluate this study?
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Chapter 1 Solutions
Introduction to Statistics and Data Analysis
Ch. 1.3 - Give brief definitions of the terms descriptive...Ch. 1.3 - Give brief definitions of the terms population and...Ch. 1.3 - The following conclusion from a study appeared in...Ch. 1.3 - Based on a study of 2 121 children between the...Ch. 1.3 - The student senate at a university with 15,000...Ch. 1.3 - Prob. 6ECh. 1.3 - The supervisors of a rural county are interested...Ch. 1.3 - A consumer group conducts crash tests of new model...Ch. 1.3 - A building contractor has a chance to buy an odd...Ch. 1.3 - The article Brain Shunt Tested to Treat Alzheimers...
Ch. 1.3 - In a study of whether taking a garlic supplement...Ch. 1.4 - Classify each of the following variables as either...Ch. 1.4 - Classify each of the following variables as either...Ch. 1.4 - Prob. 14ECh. 1.4 - For the following numerical variables, state...Ch. 1.4 - For each of the following situations, give a set...Ch. 1.4 - In a survey of 100 people who had recently...Ch. 1.4 - Prob. 18ECh. 1.4 - The article Feasting on Protein (AARP Bulletin,...Ch. 1.4 - ● Box Office Mojo (www.boxofficcmojo.com) tracks...Ch. 1.4 - Prob. 21ECh. 1.4 - The following display is a graph similar to one...Ch. 1.4 - Prob. 23ECh. 1.4 - Prob. 24ECh. 1.4 - Prob. 25ECh. 1.4 - Prob. 26ECh. 1.4 - The article Fliers Trapped on Tarmac Push for...Ch. 1.4 - Prob. 28ECh. 1.4 - The article Where College Students Buy Textbooks...Ch. 1.4 - Prob. 30ECh. 1.4 - Prob. 31ECh. 1 - The report Testing the Waters 2009 (nrdc.org)...Ch. 1 - The U.S. Department of Education reported that 14%...Ch. 1 - The Computer Assisted Assessment Center at the...Ch. 1 - The article Just How Safe Is That Jet? (USA TODAY,...Ch. 1 - Each year, U.S. News and World Report publishes a...Ch. 1 - Many adolescent boys aspire to be professional...
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