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 5.12, Problem 58SE
The concentration of mercury in a lake has been monitored for a number of years. Measurements taken on a weekly basis yielded an average of 1.20 mg/m3 (milligrams per cubic meter) with a standard deviation of .32 mg/m3. Following an accident at a smelter on the shore of the lake, 15 measurements produced the following mercury concentrations.
- a. Give a point estimate of the mean mercury concentration after the accident.
- b. Construct a 95% confidence interval on the mean mercury concentration after the accident. Interpret this interval.
- c. Is there sufficient evidence that the mean mercury concentration has increased since the accident? Use α = .05.
- d. Assuming that the standard deviation of the mercury concentration is .32 mg/m3, calculate the power of the test to detect mercury concentrations of 1.28, 1.32, 1.36, and 1.40.
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Chapter 5 Solutions
An Introduction to Statistical Methods and Data Analysis
Ch. 5.12 - The county government in a city that is dominated...Ch. 5.12 - In the research study on percentage of calories...Ch. 5.12 - Face masks used by firefighters often fail by...Ch. 5.12 - Refer to Exercise 5.3. Describe a process to...Ch. 5.12 - A company that manufacturers coffee for use in...Ch. 5.12 - Refer to Exercise 5.5. The engineer in charge of...Ch. 5.12 - Refer to Exercise 5.5. Because the company is...Ch. 5.12 - As part of the recruitment of new businesses, the...Ch. 5.12 - A program to reduce recidivism has been in effect...Ch. 5.12 - The susceptibility of the root stocks of a variety...
Ch. 5.12 - Prob. 11ECh. 5.12 - In any given situation, if the level of confidence...Ch. 5.12 - A biologist wishes to estimate the effect of an...Ch. 5.12 - Refer to Exercise 5.14. Suppose the mayors staff...Ch. 5.12 - Refer to Exercise 5.14. Suppose the mayors staff...Ch. 5.12 - A study is designed to test the hypotheses H0: ...Ch. 5.12 - Refer to Exercise 5.16. Graph the power curve for...Ch. 5.12 - A study was conducted of 90 adult male patients...Ch. 5.12 - Prob. 22ECh. 5.12 - A national agency sets recommended daily dietary...Ch. 5.12 - To evaluate the success of a 1-year experimental...Ch. 5.12 - Refer to Exercise 5.24. Suppose a random sample of...Ch. 5.12 - The administrator of a nursing home would like to...Ch. 5.12 - The vulnerability of inshore environments to...Ch. 5.12 - The RD department of a paint company has developed...Ch. 5.12 - Prob. 29ECh. 5.12 - A concern to public health officials is whether a...Ch. 5.12 - Prob. 31ECh. 5.12 - Prob. 32ECh. 5.12 - Prob. 33ECh. 5.12 - Provide the rejection region based on a t-test...Ch. 5.12 - A study was designed to evaluate whether the...Ch. 5.12 -
The ability to read rapidly and simultaneously...Ch. 5.12 - Refer to Exercise 5.36. Using the reading...Ch. 5.12 -
Refer to Exercise 5.36.
Does there appear to be a...Ch. 5.12 - A consumer testing agency wants to evaluate the...Ch. 5.12 -
Refer to Exercise 5.39.
Does the normality of the...Ch. 5.12 - The amount of sewage and industrial pollutants...Ch. 5.12 - A dealer in recycled paper places empty trailers...Ch. 5.12 - Prob. 47ECh. 5.12 - Prob. 48ECh. 5.12 - Prob. 49ECh. 5.12 - Prob. 50ECh. 5.12 - Prob. 51ECh. 5.12 - Prob. 52ECh. 5.12 - Prob. 53ECh. 5.12 - Prob. 54ECh. 5.12 - Prob. 55ECh. 5.12 - Prob. 56ECh. 5.12 - Prob. 57SECh. 5.12 - The concentration of mercury in a lake has been...Ch. 5.12 -
In a standard dissolution test for tablets of a...Ch. 5.12 - Prob. 60SECh. 5.12 -
Over the past 5 years, the mean time for a...Ch. 5.12 - If a new process for mining copper is to be put...Ch. 5.12 - Prob. 63SECh. 5.12 - Prob. 64SECh. 5.12 - Prob. 65SECh. 5.12 - Prob. 66SECh. 5.12 - Prob. 67SECh. 5.12 - Prob. 68SECh. 5.12 - Prob. 69SECh. 5.12 - Prob. 70SECh. 5.12 - Prob. 71SECh. 5.12 - Prob. 73SECh. 5.12 - Prob. 74SECh. 5.12 - Prob. 75SECh. 5.12 - Prob. 76SE
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