Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Textbook Question
Chapter 11.2, Problem 77E
RBC Transfusions. In the article “Reduction in Red Blood Cells Transfusions Among Preterm Infants: Results of a Randomized Trial With an In-Line Blood Gas and Chemistry Monitor” (Pediatrics, Vol. 115, Issue 5, pp. 1299–1306), J. Widness et al. examined extremely premature infants who develop anemia caused by intensive laboratory blood testing and multiple red blood cell (RBC) transfusions. The goal of the study was to reduce the number of RBC transfusions. Two groups were studied, a control group and a monitor group (which used the in-line blood gas and chemistry monitor). Data on hemoglobin level, in grams per liter (g/L), based on the results of the study, are provided on the WeissStats site. Use the technology of your choice to solve parts (a)–(c).
- a. Do the data provide sufficient evidence to conclude that the variation in hemoglobin level is less without the inline blood gas and chemistry monitor? Perform a two-standard-deviations F-test at the 5% significance level.
- b. Use the two-standard-deviations F-interval procedure to determine a 90% confidence interval for the ratio of the population standard deviations of hemoglobin levels with and without the inline blood gas and chemistry monitor.
- c. Obtain a normal
probability plot for each sample. - d. In light of your plots in part (c), does conducting the inferences you did in parts (a) and (b) seem reasonable? Explain your answer.
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Chapter 11 Solutions
Introductory Statistics (10th Edition)
Ch. 11.1 - What is meant by saying that a variable has a...Ch. 11.1 - How are different chi-square distributions...Ch. 11.1 - Two 2-curves have degrees of freedom 12 and 20,...Ch. 11.1 - The t-table has entries for areas of 0.10, 0.05,...Ch. 11.1 - Prob. 5ECh. 11.1 - Prob. 6ECh. 11.1 - In Exercises 11.511.2, use Table VII to find the...Ch. 11.1 - Prob. 8ECh. 11.1 - Prob. 9ECh. 11.1 - Prob. 10E
Ch. 11.1 - Prob. 11ECh. 11.1 - Prob. 12ECh. 11.1 - When you use chi-square procedures to make...Ch. 11.1 - Give two situations in which making an inference...Ch. 11.1 - Prob. 15ECh. 11.1 - In each of Exercises 11.1511.20, we have provided...Ch. 11.1 - In each of Exercises 11.1511.20, we have provided...Ch. 11.1 - Prob. 18ECh. 11.1 - In each of Exercises 11.1511.20, we have provided...Ch. 11.1 - Prob. 20ECh. 11.1 - Prob. 21ECh. 11.1 - Prob. 22ECh. 11.1 - Preliminary data analyses and other information...Ch. 11.1 - Preliminary data analyses and other information...Ch. 11.1 - Prob. 25ECh. 11.1 - Prob. 26ECh. 11.1 - In Exercises 11.2711.32, use Procedure 11.2 on...Ch. 11.1 - Prob. 28ECh. 11.1 - Prob. 29ECh. 11.1 - In Exercises 11.2711.32, use Procedure 11.2 on...Ch. 11.1 - Prob. 31ECh. 11.1 - Prob. 32ECh. 11.1 - Prob. 33ECh. 11.1 - Prob. 34ECh. 11.1 - Prob. 35ECh. 11.1 - In each of Exercises 11.3311.36, use the...Ch. 11.1 - Body Temperature. A study by researchers at the...Ch. 11.1 - Dexamethasone and IQ. In the paper Outcomes at...Ch. 11.1 - Forearm Length. In 1903, K. Pearson and A. Lee...Ch. 11.1 - Prob. 40ECh. 11.2 - How many numbers of degrees of freedom does an...Ch. 11.2 - What symbol is used to denote the F-value having...Ch. 11.2 - Prob. 44ECh. 11.2 - An F-curve has df = (12, 7). What is the number of...Ch. 11.2 - Prob. 46ECh. 11.2 - Prob. 47ECh. 11.2 - In Exercises 11.4711.54, use Table VIII and, if...Ch. 11.2 - Prob. 49ECh. 11.2 - Prob. 50ECh. 11.2 - Prob. 51ECh. 11.2 - In Exercises 11.4711.54, use Table VIII and, if...Ch. 11.2 - In Exercises 11.4711.54, use Table VIII and, if...Ch. 11.2 - Prob. 54ECh. 11.2 - In using F-procedures to make inferences for two...Ch. 11.2 - Give two situations in which comparing two...Ch. 11.2 - Prob. 57ECh. 11.2 - Prob. 58ECh. 11.2 - Prob. 59ECh. 11.2 - Prob. 60ECh. 11.2 - In each of Exercises 11.5711.62, we have provided...Ch. 11.2 - Prob. 62ECh. 11.2 - Prob. 63ECh. 11.2 - Preliminary data analyses and other information...Ch. 11.2 - Prob. 65ECh. 11.2 - Preliminary data analyses and other information...Ch. 11.2 - Prob. 67ECh. 11.2 - Preliminary data analyses and other information...Ch. 11.2 - Prob. 69ECh. 11.2 - Prob. 70ECh. 11.2 - Prob. 71ECh. 11.2 - Prob. 72ECh. 11.2 - Prob. 73ECh. 11.2 - Prob. 74ECh. 11.2 - The Etruscans. Anthropologists are still trying to...Ch. 11.2 - Prob. 76ECh. 11.2 - RBC Transfusions. In the article Reduction in Red...Ch. 11.2 - Prob. 79ECh. 11 - What distribution is used in this chapter to make...Ch. 11 - Fill in the blanks. a. A 2-curve is _____ skewed....Ch. 11 - When you use the one-standard-deviation 2-test or...Ch. 11 - Prob. 4RPCh. 11 - Prob. 5RPCh. 11 - Prob. 6RPCh. 11 - Prob. 7RPCh. 11 - Prob. 8RPCh. 11 - What distribution is used in this chapter to make...Ch. 11 - Fill in the blanks: a. An F-curve is ____ skewed....Ch. 11 - When you use the two-standard-deviations F-test....Ch. 11 - Prob. 12RPCh. 11 - Prob. 13RPCh. 11 - Prob. 14RPCh. 11 - Prob. 15RPCh. 11 - Prob. 16RPCh. 11 - Prob. 17RPCh. 11 - Prob. 18RPCh. 11 - Prob. 19RPCh. 11 - Prob. 20RPCh. 11 - Prob. 21RPCh. 11 - Prob. 22RPCh. 11 - Prob. 23RPCh. 11 - Microwave Popcorn. Two brands of microwave...Ch. 11 - Recall from Chapter 1 (see page 34) that the Focus...Ch. 11 - At the beginning of this chapter, we discussed...
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