Intro Stats
4th Edition
ISBN: 9780321825278
Author: Richard D. De Veaux, Paul F. Velleman, David E. Bock
Publisher: PEARSON
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Textbook Question
Chapter 11, Problem 51E
Dowsing Before drilling for water, many rural homeowners hire a dowser (a person who claims to be able to sense the presence of underground water using a forked stick). Suppose we wish to set up an experiment to test one dowser’s ability. We get 20 identical containers, fill some with water, and ask him to tell which ones they are.
- a) How will we randomize this procedure?
- b) The dowser correctly identifies the contents of 12 out of 20 containers. Do you think this level of success is statistically significant? Explain.
- c) How many correct identifications (out of 20) would the dowser have to make to convince you that the forked-stick trick works? Explain.
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Chapter 11 Solutions
Intro Stats
Ch. 11.3 - At one time, a method called gastric freezing was...Ch. 11.4 - Recall the experiment about gastric freezing, an...Ch. 11 - Steroids The 1990s and early 2000s could be...Ch. 11 - Prob. 2ECh. 11 - Prob. 3ECh. 11 - Tomatoes You want to compare the tastiness and...Ch. 11 - Tips II For the experiment described in Exercise...Ch. 11 - Prob. 6ECh. 11 - Prob. 7ECh. 11 - Prob. 8E
Ch. 11 - Prob. 9ECh. 11 - Prob. 10ECh. 11 - Block that tip The driver of Exercise 3 wants to...Ch. 11 - Blocking tomatoes To obtain enough plants for the...Ch. 11 - Prob. 13ECh. 11 - Prob. 14ECh. 11 - Standardized test scores For his statistics class...Ch. 11 - Heart attacks and height Researchers who examined...Ch. 11 - Prob. 17ECh. 11 - Prob. 18ECh. 11 - Menopause Researchers studied the herb black...Ch. 11 - Honesty Coffee stations in offices often just ask...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - Omega-3 Exercise 21 describes an experiment that...Ch. 11 - Insomnia Exercise 24 describes an experiment...Ch. 11 - Omega-3, revisited Exercises 21 and 35 describe an...Ch. 11 - Insomnia, again Exercises 24 and 36 describe an...Ch. 11 - Omega-3, finis Exercises 21, 35, and 37 describe...Ch. 11 - Insomnia, at last Exercises 24, 36, and 38...Ch. 11 - Injuries Exercise 33 describes an experiment that...Ch. 11 - Tomatoes II Describe a strategy to randomly split...Ch. 11 - Shoes A running-shoe manufacturer wants to test...Ch. 11 - Swimsuits A swimsuit manufacturer wants to test...Ch. 11 - Hamstrings Exercise 33 discussed an experiment to...Ch. 11 - Diet and blood pressure An experiment showed that...Ch. 11 - Mozart Will listening to a Mozart piano sonata...Ch. 11 - Contrast baths Contrast bath treatments use the...Ch. 11 - Prob. 49ECh. 11 - Swimming Recently, a group of adults who swim...Ch. 11 - Dowsing Before drilling for water, many rural...Ch. 11 - Healing A medical researcher suspects that giving...Ch. 11 - Reading Some schools teach reading using phonics...Ch. 11 - Gas mileage Do cars get better gas mileage with...Ch. 11 - Weekend deaths A study published in the New...Ch. 11 - Shingles A research doctor has discovered a new...Ch. 11 - Beetles Hoping to learn how to control crop damage...Ch. 11 - SAT prep Can special study courses actually help...Ch. 11 - Safety switch An industrial machine requires an...Ch. 11 - Washing clothes A consumer group wants to test the...Ch. 11 - Skydiving, anyone? A humor piece published in the...
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