An Introduction to Statistical Methods and Data Analysis
7th Edition
ISBN: 9781305269477
Author: R. Lyman Ott, Micheal T. Longnecker
Publisher: Cengage Learning
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Chapter 10.11, Problem 7E
The test for screening donated blood for the presence of the AIDS virus was developed of the test, 1,000 persons known to have AIDS and 10,000 persons known to not have AIDS were given the test. The following results were tabulated:
- a. Place a 99% confidence interval on the proportion of false positives produced by the test.
- b. Is there substantial evidence (α = .01) that the test produces less than 5% false positives.
in the 1980s. It is designed to detect antibodies, substances produced in the body of donors carrying the virus; however, it is not 100% accurate. The developer of the test claimed that the test would produce fewer than 5% false positives and fewer than 1% false negatives. In order to evaluate the accuracy
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An apple farmer inspects a large random sample of his apples and finds that 20% contain excellent worms. He wants to charge his customers extra, and claims that the 90% confidence interval for the population pro- portion of apples that contain worms has a margin of error of at most 0.01. At least how many apples did the farmer inspect?
The drug Viagra became available in the U.S. in May 1988, in the wake of an advertising campaign that was unprecedented in scope and intensity. A Gallup poll found that by the end of the first week of May, 643 out of 1,005 adults were aware that Viagra was an impotency medication.
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Yes, because more than 10 adults were aware of Viagra
Yes, because both np̂ and n(1-p̂) are greater than 10
b)Using the information from questions 1-3, suppose that p̂ is 0.40 and the standard error of p̂ is 0.10. Compute a 90% confidence interval for the proportion of adults that were aware of Viagra.
(0.2355, 0.5645)
(0.3, 0.5)
(0.2355, 0.4)
(0.3, 0.4)
A random sample of residents in city J were surveyed about whether they supported raising taxes to increase bus service for the city. From the results, a 95 percent confidence interval was constructed to estimate the proportion of people in the city who support the increase. The interval was (0.46,0.52)(0.46,0.52).
Based on the confidence interval, which of the following claims is supported?
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B) More than 60 percent of the residents support the increase.
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Chapter 10 Solutions
An Introduction to Statistical Methods and Data Analysis
Ch. 10.11 - Prob. 1ECh. 10.11 - For each of the following values for and n,...Ch. 10.11 - Prob. 3ECh. 10.11 - A random sample of 1,200 units is randomly...Ch. 10.11 - A public opinion polling agency plans to conduct a...Ch. 10.11 - The test for screening donated blood for the...Ch. 10.11 - National public opinion polls are often based on...Ch. 10.11 - Prob. 17ECh. 10.11 - A large retail lawn care dealer currently provides...Ch. 10.11 - Prob. 20E
Ch. 10.11 - Sludge is a dried product remaining from processed...Ch. 10.11 - A political scientist is studying the impact of a...Ch. 10.11 - The quality control department of a motorcycle...Ch. 10.11 - Refer to Exercise 10.29. a. Place 95% confidence...Ch. 10.11 - The article “Positive Aspects of Caregiving”...Ch. 10.11 - A study examining bomb hits in South London during...Ch. 10.11 - The fire department in a large city is examining...Ch. 10.11 - Prob. 53ECh. 10.11 - A carcinogenicity study was conducted to examine...
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