Intro Stats
4th Edition
ISBN: 9780321825278
Author: Richard D. De Veaux, Paul F. Velleman, David E. Bock
Publisher: PEARSON
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Chapter 10.2, Problem 1JC
Various claims are often made for surveys. Why is each of the following claims not correct?
- a) It is always better to take a census than to draw a sample.
- b) Stopping students on their way out of the cafeteria is a good way to sample if we want to know about the quality of the food there.
- c) We drew a sample of 100 from the 3000 students in a school. To get the same level of precision for a town of 30,000 residents, we’ll need a sample of 1000.
- d) A poll taken at a statistics support website garnered 12,357 responses. The majority said they enjoy doing statistics homework. With a
sample size that large, we can be pretty sure that most statistics students feel this way too. - e) The true percentage of all statistics students who enjoy the homework is called a “population statistic.”
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Chapter 10 Solutions
Intro Stats
Ch. 10.2 - Various claims are often made for surveys. Why is...Ch. 10.4 - We need to survey a random sample of the 300...Ch. 10 - Texas AM Administrators at Texas AM University...Ch. 10 - Satisfied workers The managers of a large company...Ch. 10 - AM again The president of the university plans a...Ch. 10 - Satisfied respondents The companys annual report...Ch. 10 - Sampling students A professor teaching a large...Ch. 10 - Sampling satisfaction A company hoping to assess...Ch. 10 - Sampling AM students For each scenario, identify...Ch. 10 - Satisfactory satisfaction samples For each...
Ch. 10 - Survey students What problems do you see with...Ch. 10 - Happy employees The company plans to have the head...Ch. 10 - Student samples The university administration of...Ch. 10 - Surveying employees The company of Exercise 2 is...Ch. 10 - Roper Through their Roper Reports Worldwide, GfK...Ch. 10 - Student center survey For their class project, a...Ch. 10 - Drug tests Major League Baseball tests players to...Ch. 10 - Prob. 16ECh. 10 - In Exercises 17 to 23, for the reports about...Ch. 10 - Prob. 18ECh. 10 - Prob. 19ECh. 10 - Prob. 20ECh. 10 - In Exercises 17 to 23, for the reports about...Ch. 10 - In Exercises 17 to 23, for the reports about...Ch. 10 - In Exercises 17 to 23, for the reports about...Ch. 10 - Mistaken poll A local TV station conducted a...Ch. 10 - Another mistaken poll Prior to the mayoral...Ch. 10 - Parent opinion, part 1 In a large city school...Ch. 10 - Parent opinion, part 2 Lets revisit the school...Ch. 10 - Prob. 28ECh. 10 - Prob. 29ECh. 10 - Roller coasters An amusement park has opened a new...Ch. 10 - Playground, act two The survey described in...Ch. 10 - Wording the survey Two members of the PTA...Ch. 10 - Banning ephedra An online poll on a website asked:...Ch. 10 - Survey questions Examine each of the following...Ch. 10 - More survey questions Examine each of the...Ch. 10 - Phone surveys Any time we conduct a survey, we...Ch. 10 - Cell phone survey What about drawing a random...Ch. 10 - Fuel economy Occasionally, when I fill my car with...Ch. 10 - Prob. 40ECh. 10 - Prob. 41ECh. 10 - Quality control Sammys Salsa, a small local...Ch. 10 - A fish story Concerned about reports of discolored...Ch. 10 - Prob. 44ECh. 10 - More sampling methods Consider each of these...
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