An Introduction to Statistical Methods and Data Analysis
7th Edition
ISBN: 9780357670620
Author: R. Lyman Ott; Micheal T. Longnecker
Publisher: Cengage Learning US
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Chapter 2.8, Problem 31SE
A transportation researcher is funded to estimate the proportion of automobile tires with an unsafe tread thickness in a small northern state. The researcher randomly selects one month during each of the four seasons for taking the measurements. During each of the four selected months, the researcher randomly selects 500 cars from the list of registered cars in the state and then measures the tread thickness of the four tires on each of the selected cars.
- a. What is the population of interest?
- b. What is the sampling frame?
- c. What biases if any may result from using the data from this study to obtain the estimated proportion of cars with an unsafe thread thickness?
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Chapter 2 Solutions
An Introduction to Statistical Methods and Data Analysis
Ch. 2.8 - In the following descriptions of a study,...Ch. 2.8 - In the following descriptions of a study,...Ch. 2.8 - A news report states that minority children who...Ch. 2.8 - A study was conducted to determine if the...Ch. 2.8 - Prob. 5ECh. 2.8 - A large auto parts supplier with distribution...Ch. 2.8 - The circuit judges in a rural county are...Ch. 2.8 - Prob. 8ECh. 2.8 - Time magazine, in an article in the late 1950s,...Ch. 2.8 - The New York City school district is planning a...
Ch. 2.8 - A professional society, with a membership of...Ch. 2.8 - For each of the following situations, decide what...Ch. 2.8 - For each of the following situations, decide what...Ch. 2.8 - The process engineer designed a study to evaluate...Ch. 2.8 - Prob. 15ECh. 2.8 - In the descriptions of experiments given in...Ch. 2.8 - In the descriptions of experiments given in...Ch. 2.8 - In the descriptions of experiments given in...Ch. 2.8 - A research specialist for a large seafood company...Ch. 2.8 - In Exercises 2.20–2.22, identify whether the...Ch. 2.8 - In Exercises 2.202.22, identify whether the design...Ch. 2.8 - In Exercises 2.20–2.22, identify whether the...Ch. 2.8 - A bakery wants to evaluate new recipes for carrot...Ch. 2.8 - Prob. 24SECh. 2.8 - Prob. 25SECh. 2.8 - Prob. 26SECh. 2.8 - Prob. 27SECh. 2.8 - Prob. 28SECh. 2.8 - Prob. 29SECh. 2.8 - A forester wants to estimate the total number of...Ch. 2.8 - A transportation researcher is funded to estimate...Ch. 2.8 - The department of agriculture in a midwestern...Ch. 2.8 - Prob. 33SECh. 2.8 - A Yankelovich, Skelly, and White poll taken in the...
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