Intro Stats
4th Edition
ISBN: 9780321826275
Author: Richard D. De Veaux
Publisher: PEARSON
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Chapter 16.1, Problem 1JC
A Pew Research study regarding cell phones asked about cell phone experience. One growing concern is unsolicited advertising in the form of text messages. Pew asked cell phone owners, “Have you ever received unsolicited text messages on your cell phone from advertisers?” and 17% reported that they had. Pew estimates a 95% confidence interval to be 0.17 ± 0.04, or between 13% and 21%.
Are the following statements about people who have cell phones correct interpretations of that confidence interval? Explain.
4. In Pew’s sample, somewhere between 13% and 21% of respondents reported that they had received unsolicited advertising text messages.
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Chapter 16 Solutions
Intro Stats
Ch. 16.1 - A Pew Research study regarding cell phones asked...Ch. 16.1 - Prob. 2JCCh. 16.1 - A Pew Research study regarding cell phones asked...Ch. 16.1 - Prob. 4JCCh. 16.1 - Prob. 5JCCh. 16.2 - Prob. 6JCCh. 16.2 - Prob. 7JCCh. 16.2 - Prob. 8JCCh. 16 - Prob. 1ECh. 16 - Prob. 2E
Ch. 16 - Prob. 3ECh. 16 - Prob. 4ECh. 16 - Prob. 5ECh. 16 - 6. I asked, “How’s life?” In the Gallup poll...Ch. 16 - Prob. 7ECh. 16 - Prob. 8ECh. 16 - Margin of error A TV newscaster reports the...Ch. 16 - Another margin of error A medical researcher...Ch. 16 - Conditions For each situation described below,...Ch. 16 - More conditions Consider each situation described....Ch. 16 - Conclusions A catalog sales company promises to...Ch. 16 - More conclusions In January 2002, two students...Ch. 16 - Confidence intervals Several factors are involved...Ch. 16 - Confidence intervals, again Several factors are...Ch. 16 - Cars What fraction of cars made in Japan? The...Ch. 16 - Prob. 18ECh. 16 - Prob. 19ECh. 16 - Prob. 20ECh. 16 - Prob. 21ECh. 16 - Prob. 22ECh. 16 - 23. Contributions, please The Paralyzed Veterans...Ch. 16 - Take the offer First USA, a major credit card...Ch. 16 - Teenage drivers An insurance company checks police...Ch. 16 - Junk mail Direct mail advertisers send...Ch. 16 - Prob. 27ECh. 16 - Prob. 28ECh. 16 - Prob. 29ECh. 16 - Gambling A city ballot includes a local initiative...Ch. 16 - Rickets Vitamin D, whether ingested as a dietary...Ch. 16 - Teachers A 2011 Gallup poll found that 76% of...Ch. 16 - Prob. 33ECh. 16 - Back to campus ACT, Inc. reported that 74% of 1644...Ch. 16 - Deer ticks Wildlife biologists inspect 153 deer...Ch. 16 - Prob. 36ECh. 16 - Graduation Its believed that as many as 25% of...Ch. 16 - Hiring In preparing a report on the economy, we...Ch. 16 - Prob. 39ECh. 16 - Prob. 40ECh. 16 - Prob. 41ECh. 16 - Another pilot study During routine screening, a...Ch. 16 - Prob. 43ECh. 16 - Amendment A TV news reporter says that a proposed...
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