Introduction to Probability and Statistics
14th Edition
ISBN: 9781133103752
Author: Mendenhall, William
Publisher: Cengage Learning
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Chapter 10.5, Problem 10.43E
Healthy Teeth II Exercise 10.25 describes adental experiment conducted to investigate the effectiveness of an oral rinse used to inhibit the growth of plaqueon teeth. Subjects were divided into two groups: Onegroup used a rinse with an antiplaque ingredient, and thecontrol group used a rinse containing inactive ingredients. Suppose that the plaque growth on each person’steeth was measured after using the rinse after 4 hoursand then again after 8 hours. If you wish to estimate thedifference in plaque growth from 4 to 8 hours, shouldyou use a confidence interval based on a paired or anunpaired analysis? Explain.
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A local church is interested in determining how length of residence in the present community relates to church attendance. Using a random sample of 15 individuals, they gathered data on how many times in the previous 5 weeks each individual attended church services. The data are provided below.
Length of residence in the community
Less than 2 years
2-5 years
More than 5 years
0
0
1
1
2
3
3
3
3
4
4
4
4
5
4
Using the 5-step model, determine whether and how church attendance is related to length of residence in the community. Use 5% and 1% levels of statistical significance.
What are the assumptions for this problem?
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.
Dyslexia refers to a specific reading disability that affects 10% to 15% of the general population. A dyslexic child is defined as a child of normal or above-normal intelligence with no known organic behavioural disorders who, despite normal schooling, shows a reading lag of at least two years. A researcher proposed that dyslexia was the result of a complex visual deficit that could be immediately corrected by simply putting a blue plastic overlay on the reading material. To test this, 100 dyslexic children were randomly assigned to one of two groups, one of which read from pages with a clear plastic overlay and the other of which read from pages with a blue plastic overlay. The dependent variable was percentage correct on a multiple-choice reading comprehension test.
a) Is this an observational study or an experiment? Explain your choice. b) Why did the researcher use a clear overlay as one of the treatment groups instead of just having the children read the passage without an…
Chapter 10 Solutions
Introduction to Probability and Statistics
Ch. 10.3 - Prob. 10.1ECh. 10.3 - Prob. 10.2ECh. 10.3 - Prob. 10.3ECh. 10.3 - Prob. 10.4ECh. 10.3 - Prob. 10.5ECh. 10.3 - Prob. 10.6ECh. 10.3 - Dissolved O2 Content Industrial wastes andsewage...Ch. 10.3 - Prob. 10.8ECh. 10.3 - Prob. 10.10ECh. 10.3 - Prob. 10.11E
Ch. 10.3 - Prob. 10.12ECh. 10.3 - Prob. 10.13ECh. 10.3 - Cholesterol, continued Refer to Exercise 10.16....Ch. 10.4 - Give the number of degrees of freedom for s2, the...Ch. 10.4 - Prob. 10.19ECh. 10.4 - Prob. 10.20ECh. 10.4 - Prob. 10.21ECh. 10.4 - Prob. 10.22ECh. 10.4 - The MINITAB printout shows a test for the...Ch. 10.4 - Prob. 10.24ECh. 10.4 - Healthy Teeth Jan Lindhe conducted a studyon the...Ch. 10.4 - Prob. 10.26ECh. 10.4 - Prob. 10.27ECh. 10.4 - Disinfectants An experiment published in...Ch. 10.4 - Prob. 10.29ECh. 10.4 - Prob. 10.31ECh. 10.4 - Prob. 10.32ECh. 10.4 - Freestyle Swimmers, continued Refer toExercise...Ch. 10.4 - Prob. 10.34ECh. 10.4 - Prob. 10.35ECh. 10.5 - Prob. 10.36ECh. 10.5 - Prob. 10.37ECh. 10.5 - Prob. 10.38ECh. 10.5 - Prob. 10.39ECh. 10.5 - Runners and Cyclists II Refer to Exercise 10.27....Ch. 10.5 - Prob. 10.41ECh. 10.5 - No Left Turn An experiment was conducted to...Ch. 10.5 - Healthy Teeth II Exercise 10.25 describes adental...Ch. 10.5 - Prob. 10.44ECh. 10.5 - Prob. 10.45ECh. 10.5 - Prob. 10.46ECh. 10.5 - Prob. 10.47ECh. 10.6 - Prob. 10.49ECh. 10.6 - Prob. 10.50ECh. 10.6 - A random sample of size n=7 from a...Ch. 10.6 - Prob. 10.54ECh. 10.6 - Prob. 10.56ECh. 10.7 - Prob. 10.58ECh. 10.7 - Prob. 10.59ECh. 10.7 - Prob. 10.60ECh. 10.7 - Prob. 10.63ECh. 10.7 - Prob. 10.64ECh. 10.7 - Prob. 10.65ECh. 10.7 - Prob. 10.66ECh. 10 - Prob. 10.67SECh. 10 - Prob. 10.68SECh. 10 - Prob. 10.69SECh. 10 - Prob. 10.70SECh. 10 - Prob. 10.71SECh. 10 - Prob. 10.72SECh. 10 - Prob. 10.73SECh. 10 - Prob. 10.74SECh. 10 - Prob. 10.76SECh. 10 - Prob. 10.78SECh. 10 - Prob. 10.79SECh. 10 - Prob. 10.80SECh. 10 - Prob. 10.81SECh. 10 - Prob. 10.82SECh. 10 - Prob. 10.83SECh. 10 - Prob. 10.84SECh. 10 - Prob. 10.85SECh. 10 - Prob. 10.86SECh. 10 - Prob. 10.88SECh. 10 - Prob. 10.89SECh. 10 - Prob. 10.90SECh. 10 - Dieting Eight obese persons were placed on a diet...Ch. 10 - Prob. 10.93SECh. 10 - Reaction Times II Refer to Exercise10.94. Suppose...Ch. 10 - Prob. 10.96SECh. 10 - Prob. 10.97SECh. 10 - Prob. 10.98SECh. 10 - Prob. 10.99SECh. 10 - Prob. 10.101SECh. 10 - Prob. 10.105SECh. 10 - Alcohol and Altitude The effect of...Ch. 10 - Prob. 10.107SECh. 10 - Prob. 10.108SECh. 10 - Prob. 10.109SECh. 10 - Prob. 10.110SECh. 10 - Prob. 10.111SECh. 10 - Prob. 10.112SECh. 10 - Prob. 10.114SECh. 10 - Prob. 10.116SECh. 10 - Prob. 10.118SECh. 10 - Prob. 1CSCh. 10 - Prob. 2CSCh. 10 - Prob. 3CS
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