Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Chapter 13.7, Problem 22E
a Based on your answers to Exercises 13.20 and 13.21 and the comments at the end of this section, how would you expect confidence intervals computed using the results of this section to compare with related intervals that make use of the data from only one or two of the samples obtained in a one-way layout? Why?
b Refer to part (a). Is it possible that a 95% confidence interval for the
13.20 Refer to Examples 13.2 and 13.3.
a Use the portion of the data in Table 13.2 that deals only with teaching technique 1 and the method of Section 8.8 to form a 95% confidence interval for the mean score of students taught using technique 1.
b How does the length of the 95% confidence interval that you found in part (a) compare to the length of the 95% confidence interval obtained in Example 13.3?
c What is the major reason that the interval that you found in part (a) is longer than the interval given in Example 13.3?
13.21 Refer to Examples 13.2 and 13.4.
a Use the portion of the data in Table 13.2 that deals only with teaching techniques 1 and 4 and the method of Section 8.8 to form a 95% confidence interval for the difference in mean score for students taught using techniques 1 and 4.
b How does the length of the 95% confidence interval that you found in part (a) compare to the length of the 95% confidence interval obtained in Example 13.4?
c What is the major reason that the interval that you found in part (a) is longer than the interval given in Example 13.4?
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Chapter 13 Solutions
Mathematical Statistics with Applications
Ch. 13.2 - The reaction times for two different stimuli in a...Ch. 13.2 - Prob. 2ECh. 13.4 - State the assumptions underlying the ANOVA of a...Ch. 13.4 - Prob. 4ECh. 13.4 - Prob. 5ECh. 13.4 - Suppose that independent samples of sizes n1, n2,,...Ch. 13.4 - Four chemical plants, producing the same products...Ch. 13.4 - Prob. 8ECh. 13.4 - Prob. 9ECh. 13.4 - A clinical psychologist wished to compare three...
Ch. 13.4 - It is believed that women in the postmenopausal...Ch. 13.4 - If vegetables intended for human consumption...Ch. 13.4 - One portion of the research described in a paper...Ch. 13.4 - The Florida Game and Fish Commission desires to...Ch. 13.4 - Prob. 15ECh. 13.4 - An experiment was conducted to examine the effect...Ch. 13.5 - Prob. 17ECh. 13.5 - Refer to Exercise 13.17 and consider YiYi for i ...Ch. 13.5 - Refer to the statistical model for the one-way...Ch. 13.7 - Refer to Examples 13.2 and 13.3. a Use the portion...Ch. 13.7 - Refer to Examples 13.2 and 13.4. a Use the portion...Ch. 13.7 - a Based on your answers to Exercises 13.20 and...Ch. 13.7 - Refer to Exercise 13.7. a Construct a 95%...Ch. 13.7 - Prob. 24ECh. 13.7 - Prob. 25ECh. 13.7 - Prob. 26ECh. 13.7 - Prob. 27ECh. 13.7 - Prob. 28ECh. 13.7 - Prob. 29ECh. 13.7 - Prob. 30ECh. 13.7 - Prob. 31ECh. 13.7 - Prob. 32ECh. 13.7 - Prob. 33ECh. 13.7 - Prob. 34ECh. 13.7 - Prob. 35ECh. 13.8 - Prob. 36ECh. 13.8 - Prob. 37ECh. 13.8 - Prob. 38ECh. 13.8 - Prob. 39ECh. 13.8 - Prob. 40ECh. 13.9 - Prob. 41ECh. 13.9 - The accompanying table presents data on yields...Ch. 13.9 - Refer to Exercise 13.42. Why was a randomized...Ch. 13.9 - Prob. 44ECh. 13.9 - Prob. 45ECh. 13.9 - Prob. 46ECh. 13.9 - Prob. 47ECh. 13.9 - Prob. 48ECh. 13.9 - Prob. 49ECh. 13.9 - Prob. 50ECh. 13.9 - Prob. 51ECh. 13.10 - Prob. 52ECh. 13.10 - Prob. 53ECh. 13.10 - Prob. 54ECh. 13.10 - Refer to Exercise 13.46. Construct a 95%...Ch. 13.10 - Prob. 56ECh. 13.10 - Prob. 57ECh. 13.11 - Prob. 58ECh. 13.11 - Prob. 59ECh. 13.11 - Prob. 60ECh. 13.11 - Prob. 61ECh. 13.11 - Prob. 62ECh. 13.12 - Prob. 63ECh. 13.12 - Prob. 64ECh. 13.12 - Prob. 65ECh. 13.12 - Prob. 66ECh. 13.12 - Prob. 67ECh. 13.12 - Prob. 68ECh. 13.13 - Prob. 69ECh. 13.13 - Prob. 70ECh. 13.13 - Refer to Exercise 13.42. Answer part (a) by...Ch. 13.13 - Refer to Exercise 13.45. Answer part (b) by...Ch. 13 - Prob. 73SECh. 13 - Prob. 74SECh. 13 - Prob. 75SECh. 13 - Prob. 77SECh. 13 - A study was initiated to investigate the effect of...Ch. 13 - Prob. 79SECh. 13 - A dealer has in stock three cars (models A, B, and...Ch. 13 - In the hope of attracting more riders, a city...Ch. 13 - Prob. 84SECh. 13 - Prob. 85SECh. 13 - Prob. 86SECh. 13 - Prob. 87SECh. 13 - Prob. 88SECh. 13 - Prob. 89SECh. 13 - Prob. 90SECh. 13 - Prob. 92SECh. 13 - Prob. 94SE
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