researcher examines whether an over-the-counter cold medication influences mental alertness of prison wardens. A random sample of n = 16 participants is obtained, and each person is given a standard dose of the medication one hour before being tested on a simulation task. For the general population, scores on the simulation task are normally distributed with µ = 60 and σ = 8. The individuals in the

researcher examines whether an over-the-counter cold medication influences mental alertness of prison wardens. A random sample of n = 16 participants is obtained, and each person is given a standard dose of the medication one hour before being tested on a simulation task. For the general population, scores on the simulation task are normally distributed with µ = 60 and σ = 8. The individuals in the

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.1: Measures Of Center

Problem 9PPS

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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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