Find the critical value of the problem: An increase in walking has beenshown to contribute to a healthier life-style. A sedentary American takesan average of 5000 steps per day (and 65% of Americans are overweight).A group of health-conscious employees of a large health care systemvolunteered to wear pedometers for a month to record their steps. It wasfound that a random sample of 40 walkers took an average of 5430 stepsper day, and the population standard deviation is 600 steps. At alpha =0.02 can it be concluded that they walked more than the mean number of5000 steps per day? *O 2.31O 2.33O 2.28O 2.25

Given: The level of significance=α=0.02. The sample size is n=40. The population mean=μ=5000. The…

Answered: Find the critical value of the problem…

Linear Algebra: A Modern Introduction

4th Edition

ISBN:9781285463247

Author:David Poole

Publisher:David Poole

Chapter7: Distance And Approximation

Section7.3: Least Squares Approximation

Problem 31EQ

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Researchers interested in lead exposure due to car exhaust sampled the blood of 52 police officers subjected to constant inhalation of automobile exhaust fumes while working traffic enforcement in a primarily urban environment. The blood samples of these officers had an average lead concentration of 124.32 µg/l and an SD of 37.74 µg/l; a previous study of individuals from a nearby suburb, with no history of exposure, found an average blood level concentration of 35 µg/l. Write down the hypotheses that would be appropriate for testing if the police officers appear to have been exposed to a higher concentration of lead. Explicitly state and check all conditions necessary for inference on these data. Test the hypothesis that the downtown police officers have a higher lead exposure than the group in the previous study. Interpret your results in context. Based on your preceding result, without performing a calculation, would a 99% confidence interval for the average blood concentration…
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Researchers interested in lead exposure due to car exhaust sampled the blood of 52 police officers subjected to constant inhalation of automobile exhaust fumes while working traffic enforcement in a primarily urban environment. The blood samples of these officers had an average lead concentration of 124.32 µg/l and a SD of 37.74 µg/l; a previous study of individuals from a nearby suburb, with no history of exposure, found an average blood level concentration of 35 µg/l. Test the hypothesis that the downtown police officers have a higher lead exposure than the group in the previous study. Interpret your results in context. Based on your preceding result, without performing a calculation, would a 99% confidence interval for the average blood concentration level of police officers contain 35 µg/l? Based on your preceding result, without performing a calculation, would a 99% confidence interval for this difference contain 0? Explain why or why not.
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To deal with the phenomenon of alpha inflation when doing multiple t-tests, what post-hoc tests such as the Bonferroni Correction do is _____. * Divide the critical value of t by the number of comparisons Multiply the alpha by the number of comparisons Divide the alpha level by the number of comparisons Multiply the critical value of t by the number of comparisons

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