Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Question
Chapter 15.6, Problem 28E
To determine
Check whether the data provide sufficient evidence to indicate that rats receiving the antitoxin tended to survive longer after chemotherapy than those not receiving the antitoxin.
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A pharmaceutical company conducts an experiment to test the effect of a new
cholesterol medication. The company selects 15 subjects randomly from a larger
population. Each subject is randomly assigned to one of three treatment groups.
Within each treatment group, subjects receive a different dose of the new medication.
In Group 1, subjects receive 0 mg/day; in Group 2, 50 mg/day; and in Group 3, 100
mg/day.
After 30 days, doctors measure the cholesterol level of each subject. The results for all
15 subjects appear in the table below:
Dosage
Group 1
Group 2
Group 3
O mg
50 mg
100 mg
210
210
180
240
240
210
270
250
220
270
270
210
300
270
240
(a) Perform an appropriate test to test whether there are differences among the mean
cholesterol level by three different doses of the new medication at 5% level of
significance.
(b) Compute the p-value and indicate whether it leads to the same conclusion.
A study examined the impact of THC, the active ingredient in marijuana, on various physiological and psychological
variables. The study recruited a sample of 18 young adults who were habitual marijuana smokers. Participants came to the
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cigarette: one with 3.9% THC, one with 1.8% THC, and one with no THC, a placebo. The order of the conditions was
randomized and participants were not told how much THC was in the cigarette they smoked until after all the data were
collected. This is an example of
a completely randomized experiment.
O a case-control observational study.
an anecdotal evidence.
O a matched pairs or repeated measures experiment.
Incorrect
Researchers investigated the possible beneficial effect on heart health of drinking black tea and whether adding milk to the tea reduces any possible benefit. Twenty-four volunteers were randomly assigned to one of three groups. Every day for a month, participants in group 1 drank two cups of hot black tea without milk, participants in group 2 drank two cups of hot black tea with milk, and participants in group 3 drank two cups of hot water but no tea. At the end of the month, the researchers measured the change in each of the participants’ heart health.
Did the researchers conduct an experiment or an observational study? Explain.
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Chapter 15 Solutions
Mathematical Statistics with Applications
Ch. 15.3 - What significance levels between = .01 and = .15...Ch. 15.3 - Prob. 2ECh. 15.3 - Clinical data concerning the effectiveness of two...Ch. 15.3 - Prob. 4ECh. 15.3 - New food products are frequently subjected to...Ch. 15.3 - On clear, cold nights in the central Florida...Ch. 15.3 - A psychological experiment was conducted to...Ch. 15.3 - Refer to Exercise 12.15. Using the sign test, do...Ch. 15.3 - Prob. 9ECh. 15.4 - The accompanying table gives the scores of a group...
Ch. 15.4 - Refer to Exercise 15.4. What answers are obtained...Ch. 15.4 - Refer to Exercise 15.6(a). Answer the question by...Ch. 15.4 - Eight subjects were asked to perform a simple...Ch. 15.4 - Two methods, A and B, for controlling traffic were...Ch. 15.4 - Dental researchers have developed a new material...Ch. 15.4 - Refer to Exercise 12.16. With = .01, use the...Ch. 15.4 - Suppose that Y1, Y2,, Yn is a random sample from a...Ch. 15.4 - The spokesperson for an organization supporting...Ch. 15.6 - Find the p-values associated with each of the...Ch. 15.6 - In some tests of healthy, elderly men, a new drug...Ch. 15.6 - Two plastics, each produced by a different...Ch. 15.6 - Prob. 24ECh. 15.6 - Prob. 25ECh. 15.6 - Prob. 26ECh. 15.6 - Prob. 27ECh. 15.6 - Prob. 28ECh. 15.7 - The table that follows contains data on the leaf...Ch. 15.7 - Prob. 30ECh. 15.7 - Three different brands of magnetron tubes (the key...Ch. 15.7 - An experiment was conducted to compare the length...Ch. 15.7 - Prob. 33ECh. 15.7 - Prob. 34ECh. 15.7 - Prob. 35ECh. 15.8 - In a study of palatability of antibiotics for...Ch. 15.8 - Prob. 38ECh. 15.8 - Prob. 39ECh. 15.8 - A serious drought-related problem for farmers is...Ch. 15.8 - Prob. 41ECh. 15.8 - Prob. 42ECh. 15.8 - Prob. 43ECh. 15.8 - Prob. 44ECh. 15.8 - Prob. 45ECh. 15.9 - Prob. 46ECh. 15.9 - Prob. 47ECh. 15.9 - Prob. 48ECh. 15.9 - Prob. 49ECh. 15.9 - Prob. 50ECh. 15.9 - Prob. 52ECh. 15.10 - Prob. 53ECh. 15.10 - Prob. 54ECh. 15.10 - Prob. 55ECh. 15.10 - Prob. 56ECh. 15.10 - Prob. 57ECh. 15.10 - Prob. 58ECh. 15.10 - Refer to Exercise 11.4. Regard both book and...Ch. 15.10 - Prob. 60ECh. 15 - Prob. 62SECh. 15 - Prob. 63SECh. 15 - Prob. 64SECh. 15 - Prob. 65SECh. 15 - Prob. 67SECh. 15 - Prob. 69SECh. 15 - Prob. 70SECh. 15 - Prob. 71SECh. 15 - Prob. 72SECh. 15 - Prob. 74SECh. 15 - Prob. 75SECh. 15 - Prob. 76SECh. 15 - Prob. 77SECh. 15 - Prob. 78SE
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