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 27E
The vulnerability of inshore environments to contamination due to urban and industrial expansion in Mombasa is discussed in the paper “Metals, Petroleum Hydrocarbons and Organochlorines in Inshore Sediments and Waters on Mombasa, Kenya” [Marine Pollution Bulletin (1997) 34:570–577]. A geochemical and oceanographic survey of the inshore waters of Mombasa, Kenya, was undertaken during the period from September 1995 to January 1996. In the survey, suspended particulate matter and sediment were collected from 48 stations within Mombasa’s estuarine creeks. The concentrations of major oxides and 13 trace elements were determined for a varying number of cores at each of the stations. In particular, the lead concentrations in suspended particulate matter (mg kg−1 dry weight) were determined at 37 stations. The researchers were interested in determining whether the average lead concentration was greater than 30 mg kg−1 dry weight. The data are given in the following table along with summary statistics and a normal probability plot.
Lead concentrations (mg kg−1 dry weight) from 37 stations in Kenya
- a. Is there sufficient evidence (α = .05) in the data that the
mean lead concentration exceeds 30 mg kg−1 dry weight? - b. What is the probability of a Type II error if the actual mean concentration is 50?
- c. Do the data appear to have a
normal distribution ? - d. Based on your answer in (c), is the
sample size large enough for the test procedures to be valid? Explain.
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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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