EBK PROBABILITY AND STATISTICS FOR ENGI
9th Edition
ISBN: 8220102958432
Author: DEVORE
Publisher: CENGAGE L
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Chapter 15.4, Problem 25E
To determine
Test equality of the three population means using Kruskal-Wallis test.
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“Passive and Active Smoke” in Appendix B includes cotinine levels measured in a group of nonsmokers exposed to tobacco smoke (n = 40, Mean = 60.58 ng>mL, s = 138.08 ng>mL) and a group of nonsmokers not exposed to tobacco smoke (n = 40, Mean = 16.35 ng>mL, s = 62.53 ng>mL). Cotinine is a metabolite of nicotine, meaning that when nicotine is absorbed by the body, cotinine is produced. Use a 0.05 significance level to test the claim that nonsmokers exposed to tobacco smoke have a higher mean cotinine level than nonsmokers not exposed to tobacco smoke.
Based on your hypothesis tests and confidence intervals, what do you conclude about the effects of second hand smoke? Why?
“Passive and Active Smoke” in Appendix B includes cotinine levels measured in a group of nonsmokers exposed to tobacco smoke (n = 40, Mean = 60.58 ng>mL, s = 138.08 ng>mL) and a group of nonsmokers not exposed to tobacco smoke (n = 40, Mean = 16.35 ng>mL, s = 62.53 ng>mL). Cotinine is a metabolite of nicotine, meaning that when nicotine is absorbed by the body, cotinine is produced. Use a 0.05 significance level to test the claim that nonsmokers exposed to tobacco smoke have a higher mean cotinine level than nonsmokers not exposed to tobacco smoke.
1. Construct a confidence interval estimate of the difference betwen the mean continen levels fo the two groups of nonsmokers. What confidence level would be appropriate?
2. Find the margin of error E using the formula.
3. What is the confidence interval? Explain the meaning of the confidence interal and what the limit represents.
In the article “Assessment of Dermatopharmacokinetic Approach in the Bioequivalence Determination of Topical Tretinoin Gel Products” (L. Pershing, J. Nelson, et al., Journal of the American Academy of Dermatology, 2003:740-751), measurements of the concentration of an anti-fungal gel, in ng per square centimeter of skin, were made one hour after application for 49 individuals. Following are the results. The authors claim that these data are well-modeled by a lognormal distribution. Construct an appropriate probability plot, and use it to determine whether the data support this claim. 132.44 76.73258.46177.46 73.01130.62235.63 107.54 75.95 70.37 88.76104.00 19.07174.30 82.87 68.73 41.47120.44136.52 82.46 67.04 96.92 93.26 72.92138.15 82.43245.41104.68 82.53122.59147.12129.82 54.83 65.82 75.24 135.52132.21 85.63135.79 65.98349.71 77.84 89.19102.94166.11168.76155.20 44.35202.51 Figure 4.23 (page 288) shows that nonnormal data can sometimes be made approximately normal by applying an…
Chapter 15 Solutions
EBK PROBABILITY AND STATISTICS FOR ENGI
Ch. 15.1 - Give as much information as you can about the...Ch. 15.1 - Here again is the data on expense ratio (%) for a...Ch. 15.1 - The accompanying data is a subset of the data...Ch. 15.1 - A random sample of 15 automobile mechanics...Ch. 15.1 - Both a gravimetric and a spectrophotometric method...Ch. 15.1 - Reconsider the situation described in Exercise 39...Ch. 15.1 - Use the large-sample version of the Wilcoxon test...Ch. 15.1 - Reconsider the port alcohol content data from...Ch. 15.1 - Prob. 9ECh. 15.2 - Prob. 10E
Ch. 15.2 - Prob. 11ECh. 15.2 - The article A Study of Wood Stove Particulate...Ch. 15.2 - The urinary fluoride concentration (parts per...Ch. 15.2 - Prob. 14ECh. 15.2 - The article Measuring the Exposure of Infants to...Ch. 15.2 - Prob. 16ECh. 15.3 - Prob. 17ECh. 15.3 - Compute the 99% signed-rank interval for true...Ch. 15.3 - Prob. 19ECh. 15.3 - Prob. 20ECh. 15.3 - Prob. 21ECh. 15.3 - Compute a 99% CI for 1 2 using the data in...Ch. 15.4 - The accompanying data refers to concentration of...Ch. 15.4 - Prob. 24ECh. 15.4 - Prob. 25ECh. 15.4 - Prob. 26ECh. 15.4 - In an experiment to study the way in which...Ch. 15 - The article Effects of a Rice-Rich Versus...Ch. 15 - Prob. 29SECh. 15 - The given data on phosphorus concentration in...Ch. 15 - Prob. 31SECh. 15 - Prob. 32SECh. 15 - The sign test is a very simple procedure for...Ch. 15 - Prob. 34SECh. 15 - Prob. 35SECh. 15 - Prob. 36SE
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