INTRODUCTION TO STATISTICS & DATA ANALYS
6th Edition
ISBN: 9780357420447
Author: PECK
Publisher: CENGAGE L
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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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A study of “adverse symptoms” in users of over-the-counter pain relief medications assigned subjects at random toone of two common pain relievers: acetaminophen and ibuprofen. In all, 650 subjects took acetaminophen, and 44experienced some adverse symptom. Of the 347 subjects who took ibuprofen, 49 had an adverse symptom. Is thisconvincing evidence that the two pain relievers differ in the proportion of people who experience an adverse symptom?
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 & DATA ANALYS
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 - The National Retail Federation used data from a...Ch. 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 - 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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