Elementary Statistics ( 3rd International Edition ) Isbn:9781260092561

3rd Edition

ISBN: 9781259969454

Author: William Navidi Prof.; Barry Monk Professor

Publisher: McGraw-Hill Education

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Chapter 1.3, Problem 30E

Another Salk Vaccine Trial: Another study of the Salk vaccine, conducted at the same time as the trial described in Exercise 29, used a different design. In this study, approximately 350,000 second graders were invited to participate. About 225,000 did so, and the other 125,000 refused. All of the participating second graders received the vaccine. The control group consisted of approximately 725,000 first and third graders.

They were not given any placebo, so no consent was necessary.

Was this a randomized experiment?
Was it double-blind?
The treatment group consisted of children who had consent to participate. The control group consisted of all first and third graders. It turned out that the results of this study seriously underestimated the effectiveness of the vaccine. Use the information provided in Exercise 29(c) to explain why.

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Chapter 1.3, Problem 29E

Chapter 1.3, Problem 31E

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Elementary Statistics ( 3rd International Edition ) Isbn:9781260092561

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Solution Summary: The author explains the difference between randomized experiment and observational study.

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