Mathematical Statistics with Applications

7th Edition

ISBN: 9780495110811

Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer

Publisher: Cengage Learning

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.

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Textbook Question

Chapter 10.6, Problem 55E

A check-cashing service found that approximately 5% of all checks submitted to the service were bad. After instituting a check-verification system to reduce its losses, the service found that only 45 checks were bad in a random sample of 1124 that were cashed. Does sufficient evidence exist to affirm that the check-verification system reduced the proportion of bad checks? What attained significance level is associated with the test? What would you conclude at the α = .01 level?

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Chapter 10.6, Problem 54E

Chapter 10.6, Problem 56E

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Chapter 10 Solutions

Mathematical Statistics with Applications

Ch. 10.2 - Define and for a statistical test of hypotheses.Ch. 10.2 - An experimenter has prepared a drug dosage level...Ch. 10.2 - Refer to Exercise 10.2. a Find the rejection...Ch. 10.2 - Suppose that we wish to test the null hypothesis...Ch. 10.2 - Let Y1 and Y2 be independent and identically...Ch. 10.2 - We are interested in testing whether or not a coin...Ch. 10.2 - True or False Refer to Exercise 10.6. a The level...Ch. 10.2 - A two-stage clinical trial is planned for testing...Ch. 10.3 - A survey published in the American Journal of...Ch. 10.3 - The hourly wages in a particular industry are...

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Solution Summary: The author states whether the results provide sufficient evidence to indicate that the check-verification system reduced the proportion of bad checks.

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