4th Edition

ISBN: 9780321826275

Author: Richard D. De Veaux

Publisher: PEARSON

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In a 2-proportion test, two separate proportions are measured at the same time, and their similarity is evaluated. It is also known as a 2-proportion z-test, and a comparison of two different proportions is done in this method.

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Textbook Question

Chapter 11.4, Problem 2JC

Recall the experiment about gastric freezing, an old method for treating peptic ulcers that you read about in the first Just Checking. Doctors would insert an inflatable bladder down the patient’s esophagus and into the stomach and then pump in a cold liquid. A major insurance company now states that it doesn’t cover this treatment because “double-blind, controlled clinical trials” failed to demonstrate that gastric freezing was effective.

a) What does it mean that the experiment was double-blind?
b) Why would you recommend a placebo control?
c) Suppose that researchers suspected that the effectiveness of the gastric freezing treatment might depend on whether a patient had recently developed the peptic ulcer or had been suffering from the condition for a long time. How might the researchers have designed the experiment?

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Chapter 11.3, Problem 1JC

Chapter 11, Problem 1E

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Chapter 11 Solutions

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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. 2E Ch. 11 - Prob. 3E Ch. 11 - Tomatoes You want to compare the tastiness and...Ch. 11 - Tips II For the experiment described in Exercise...Ch. 11 - Prob. 6E Ch. 11 - Prob. 7E Ch. 11 - Prob. 8E

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Solution Summary: The author explains the meaning of 'double blinding' and the use of placebo in an experiment.

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