Introductory Statistics, Books a la Carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (10th Edition)
10th Edition
ISBN: 9780134270364
Author: Neil A. Weiss
Publisher: PEARSON
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Textbook Question
Chapter 11, Problem 1FDA
Recall from Chapter 1 (see page 34) that the Focus database and Focus sample contain information on the undergraduate students at the University of Wisconsin - Eau Claire (UWEC). Now would be a good time for you to review the discussion about these data sets.
Open the Focus sample worksheet (FocusSample) in the technology of your choice and then do the following.
- a. At the 5% significance level, do the data provide sufficient evidence to conclude that the standard deviation of ACT composite scores of all UWEC undergraduates differs from 3 points?
- b. Determine and interpret a 95% confidence interval for the standard deviation of ACT composite scores of all UWEC undergraduates.
- c. Obtain a normal
probability plot and a box plot of the ACT composite scores of the sampled UWEC undergraduates. - d. Based on your results from part (c), do you think that performing the inferences in parts (a) and (b) is reasonable? Explain your answer.
- e. At the 5% significance level, do the data provide sufficient evidence to conclude that the standard deviations of ACT English scores and ACT math scores differ for UWEC undergraduates?
- f. Determine and interpret a 95% confidence interval for the ratio of the standard deviation of ACT English scores to the standard deviation of ACT math scores for UWEC undergraduates.
- g. Obtain normal probability plots and boxplots of the ACT English scores and the ACT math scores of the sampled UWEC undergraduates.
- h. Based on your results from part (g), do you think that performing the inference in parts (e) and (f) is reasonable? Explain your answer.
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Chapter 11 Solutions
Introductory Statistics, Books a la Carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (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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