Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Textbook Question
Chapter 13.7, Problem 21E
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?
Table 13.2 Data for Example 13.2
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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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