Introduction To Statistics And Data Analysis
Introduction To Statistics And Data Analysis
6th Edition
ISBN: 9781337793612
Author: PECK, Roxy.
Publisher: Cengage Learning,
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Textbook Question
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.

  1. a. What were the researchers trying to learn? What questions motivated their research?
  2. 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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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.† 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. Do you think that the study was conducted in a reasonable way? What additional information would you want in order to evaluate this study? (Select all that apply.)   A) whether the patients knew which treatment they were receiving B) whether the patients were randomly assigned to the treatments C) whether the patient's last name started with A through M D) whether the patient's cold lasted more than a week E) whether the experiment was conducted on a sufficient number of patients so that the differences observed could not be attributed to chance
In a number of pharmaceutical studies volunteers who take placebos but they are told they have taken a cold remedy report the following side effects head ache 25%, drowsiness 7%, stomach upset 4%, no side effects 84%.a random sample of 250 people who were given a placebo but who thought they have taken an anti inflammatory reported whether they had experienced each of the side effects. Do the data presented in the table provide enough evidence to infer that the reported side effects of placebo for an anti inflammatory differ from that of a cold remedy? Use 10% significance level. Side effects             number of people  Headache                10 Drowsiness                 19 Stomach upset           6 No side effect             215

Chapter 1 Solutions

Introduction To Statistics And Data Analysis

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 - For the following numerical variables, state...Ch. 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 - The Gallup report More Americans Say Real Estate...Ch. 1.4 - An article in the New Times San Luis Obispo...Ch. 1.4 - Box Office Mojo (boxofficemojo.com) tracks movie...Ch. 1.4 - The report With Their Whole Lives Ahead of Them...Ch. 1.4 - The following display is a graph similar to one...Ch. 1.4 - The accompanying table gives the total number...Ch. 1.4 - Heal the Bay is an environmental organization that...Ch. 1.4 - The report referenced in the previous exercise...Ch. 1.4 - The U.S. Department of Health and Human Services...Ch. 1.4 - Example 1.5 gave the accompanying data on violent...Ch. 1.4 - The article Fliers Trapped on Tarmac Push for...Ch. 1.4 - The report Trends m Community Colleges...Ch. 1.4 - The article Where College Students Buy Textbooks...Ch. 1.4 - Prob. 31ECh. 1.4 - In the United States, movies are rated by the...Ch. 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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