Elementary Statistics (Text Only)
2nd Edition
ISBN: 9780077836351
Author: Author
Publisher: McGraw Hill
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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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II Consider the following data matrix X:
X1
X2
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0.4
0.2 0.5
0.5
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10.1
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What will the resulting clusters be when using the k-Means method with k = 2. In your own words, explain why this result is
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PS
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Screen A (12) Screen B (12)
8
037
34
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92 71689
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Chapter 1 Solutions
Elementary Statistics (Text Only)
Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 7—12, fill in each blank with the...Ch. 1.1 - In Exercises 13—16, determine whether the...Ch. 1.1 - In Exercises 13—16, determine whether the...Ch. 1.1 - In Exercises 13—16, determine whether the...Ch. 1.1 - In Exercises 13—16, determine whether the...
Ch. 1.1 - In Exercises 17—20, determine whether the number...Ch. 1.1 - In Exercises 17—20, determine whether the number...Ch. 1.1 - In Exercises 17—20, determine whether the number...Ch. 1.1 - In Exercises 17—20, determine whether the number...Ch. 1.1 - Exercises 21—24 refer to the population of...Ch. 1.1 - Exercises 21—24 refer to the population of...Ch. 1.1 - Exercises 21—24 refer to the population of...Ch. 1.1 - Exercises 21—24 refer to the population of...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - In Exercises 25—36, identify the kind of sample...Ch. 1.1 - Computer network: Every third day, a computer...Ch. 1.1 - Smartphone apps: A smartphone app produces a...Ch. 1.1 - Youre giving me a headache: A pharmaceutical...Ch. 1.1 - Pay more for recreation? 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