Probability and Statistics for Engineering and the Sciences STAT 400 - University Of Maryland
9th Edition
ISBN: 9781305764477
Author: Jay L. Devore
Publisher: Cengage Learning
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Textbook Question
Chapter 6.1, Problem 11E
Of n1 randomly selected male smokers, X1 smoked filter cigarettes, whereas of n2 randomly selected female smokers. X2 smoked filter cigarettes. Let p1 and p2 denote the probabilities that a randomly selected male and female, respectively, smoke filter cigarettes.
- a. Show that (X1/n1) - (X2/n2) is an unbiased estimator for p1 - p2. [Hint: E(X) = nipi for i = 1, 2.]
- b. What is the standard error of the estimator in part (a)?
- c. How would you use the observed values x1 and x2 to estimate the standard error of your estimator?
- d. If n1 = n2 = 200, x1 = 127, and x2 = 176, use the estimator of part (a) to obtain an estimate of p1 - p2.
- e. Use the result of part (c) and the data of part (d) to estimate the standard error of the estimator.
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Chapter 6 Solutions
Probability and Statistics for Engineering and the Sciences STAT 400 - University Of Maryland
Ch. 6.1 - The accompanying data on flexural strength (MPa)...Ch. 6.1 - The National Health and Nutrition Examination...Ch. 6.1 - Consider the following sample of observations on...Ch. 6.1 - The article from which the data in Exercise 1 was...Ch. 6.1 - As an example of a situation in which several...Ch. 6.1 - Urinary angiotensinogen (AGT) level is one...Ch. 6.1 - a. A random sample of 10 houses in a particular...Ch. 6.1 - In a random sample of 80 components of a certain...Ch. 6.1 - Each of 150 newly manufactured items is examined...Ch. 6.1 - Using a long rod that has length , you are going...
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