2. Every road has one at some point-construction zones that have much lower speed limits.To see if drivers obey these lower speed limits, a police officer used a radar gun tomeasure the speed (in miles per hour, or mph) of a random sample of 10 drivers in a 25 mphconstruction zone. Here are the results:21 30 30 29 25 27 34(a) Can we conclude that the average speed of drivers in this construction zone is greaterthan the posted 25 mph speed limit?Hypotheses:Conditions:Mechanics:Conclusion:2733 32(b) Given your conclusion in part (a), which kind of mistake-a Type I or a Type II error-could you have made? Explain what this mistake means in this context.

The given sample observation of the speed of drivers (in mph) is: 27 33 32 21 30 30 29 25 27 34…

Answered: 2. Every road has one at some…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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The price of a share of stock divided by the company's estimated future earnings per share is called the P/E ratio. High P/E ratios usually indicate "growth" stocks, or maybe stocks that are simply overpriced. Low P/E ratios indicate "value" stocks or bargain stocks. A random sample of 51 of the largest companies in the United States gave the following P/E ratios†. 11 35 19 13 15 21 40 18 60 72 9 20 29 53 16 26 21 14 21 27 10 12 47 14 33 14 18 17 20 19 13 25 23 27 5 16 8 49 44 20 27 8 19 12 31 67 51 26 19 18 32 (a) Use a calculator with mean and sample standard deviation keys to find the sample mean x and sample standard deviation s. (Round your answers to four decimal places.) x = s = (b) Find a 90% confidence interval for the P/E population mean ? of all large U.S. companies. (Round your answers to one decimal place.) lower limit upper limit (c) Find a 99% confidence interval for the P/E population mean ? of all large U.S.…
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Several methods of estimating the number of seeds in soil samples have been developed by ecologists. An article gave the accompanying data on the number of seeds detected by the direct method and by the stratified method for 27 soil specimens. Specimen Direct Stratified 1 21 7 2 34 38 3 0 7 4 60 58 5 20 54 6 61 61 7 40 27 8 7 7 9 14 7 10 94 100 11 1 0 12 67 58 13 78 67 14 21 54 Specimen Direct Stratified 15 34 27 16 0 0 17 38 38 18 18 14 19 94 94 20 1 14 21 40 47 22 21 21 23 0 0 24 7 14 25 14 40 26 18 14 27 40 78 Do the data provide sufficient evidence to conclude that the mean number of seeds detected differs for the two methods? Test the relevant hypotheses using ? = 0.05. (Use ?direct − ?stratified.) Find the test statistic. (Round your answer to two decimal places.) t = Find the df. (Round your answer down to the nearest whole number.) df = Use technology to find the P-value. (Round your answer to four…
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Several methods of estimating the number of seeds in soil samples have been developed by ecologists. An article gave the accompanying data on the number of seeds detected by the direct method and by the stratified method for 27 soil specimens. Specimen Direct Stratified 1 21 6 2 32 38 3 0 6 4 60 58 5 20 52 6 61 61 7 40 26 8 6 6 9 12 6 10 92 100 11 1 0 12 66 58 13 78 66 14 21 52 Specimen Direct Stratified 15 32 26 16 0 0 17 38 38 18 18 12 19 92 92 20 1 12 21 40 46 22 21 21 23 0 0 24 6 12 25 12 40 26 18 12 27 40 78 Do the data provide sufficient evidence to conclude that the mean number of seeds detected differs for the two methods? Test the relevant hypotheses using ? = 0.05. (Use ?direct − ?stratified.) Find the test statistic. (Round your answer to two decimal places.) t = Find the df. (Round your answer down to the nearest whole number.) df = Use technology to find the P-value. (Round your answer to four…

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