Fundamentals of Biostatistics
8th Edition
ISBN: 9781305268920
Author: Bernard Rosner
Publisher: Cengage Learning
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Textbook Question
Chapter 8, Problem 10P
The mean ±1 sd of ln [calcium intake (mg)] among 25 females, 12 to 14 years of age, below the poverty level is 6.56 ± 0.64. Similarly, the mean ± 1 sd of ln [calcium intake (mg)] among 40 females, 12 to 14 years of age, above the poverty level is 6.80 ± 0.76.
Suppose 50 girls above the poverty level and 50 girls below the poverty level are recruited for the study. How much power will the study have of finding a significant difference using a two-sided test with α = .05, assuming that the population parameters are the same as the sample estimates in Problem 8.2?
Test for a significant difference between the variances of the two groups.
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The mean ±1 sd of ln [calcium intake (mg)] among 25 females, 12 to 14 years of age, below the poverty level is 6.56 ± 0.64. Similarly, the mean ± 1 sd of ln [calcium intake (mg)] among 40 females, 12 to 14 years of age, above the poverty level is 6.80 ± 0.76.
Compute a 95% CI for the difference in means between the two groups.
A physician wants to test if temperature has an effect on heart rate. In order to do this, she compares the heart rates in beats per minute of several random volunteers after a period of time in a room with a temperature of 50∘F and after a period of time in a room with a temperature of 75∘F. Suppose that data were collected for a random sample of 11 volunteers, where each difference is calculated by subtracting the heart rate in beats per minute in the 50∘F room from the heart rate in beats per minute in the 75∘F room. Assume that the populations are normally distributed. The physician uses the alternative hypothesis Ha:μd≠0. Suppose the test statistic t is computed as t≈5.627, which has 10 degrees of freedom. What range contains the p-value?
A physician wants to test if temperature has an effect on heart rate. In order to do this, she compares the heart rate in beats per minute of several random volunteers after a period of time in a room with a temperature of 50∘F and after a period of time in a room with a temperature of 75∘F. Suppose that data were collected for a random sample of 11 volunteers, where each difference is calculated by subtracting the heart rate in beats per minute in the 50∘F room from the heart rate in beats per minute in the 75∘F room. Assume that the populations are normally distributed. The test statistic is t≈5.627, α=0.05, the corresponding rejection regions are t<−2.228 and t>2.228, the null hypothesis is H0:μd=0, and the alternative hypothesis is Ha:μd≠0.
Which of the following statements are accurate for this hypothesis test in order to evaluate the claim that the true mean difference between the heart rate in the 75∘F room and the heart rate in the 50∘F room is significantly not equal to…
Chapter 8 Solutions
Fundamentals of Biostatistics
Ch. 8 - Find the lower 2.5th percentile of an F...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...
Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - Refer to the data in Table 2.13. Table 2.13...Ch. 8 - Refer to the data in Table 2.13. What is the...Ch. 8 - Refer to the data in Table 2.13. Perform the...Ch. 8 - Refer to the data in Table 2.13. What is the...Ch. 8 - Refer to the data in Table 2.13. Compute a 95% CI...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - A study in Pittsburgh measured various...Ch. 8 - A study in Pittsburgh measured various...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - Prob. 31PCh. 8 - Prob. 32PCh. 8 - Prob. 33PCh. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - Prob. 38PCh. 8 - 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Prob. 69PCh. 8 - An experiment was conducted to examine the...Ch. 8 - An experiment was conducted to examine the...Ch. 8 - An experiment was conducted to examine the...Ch. 8 - Prob. 73PCh. 8 - Prob. 74PCh. 8 - Prob. 75PCh. 8 - Prob. 77PCh. 8 - A study was performed looking at the effect of...Ch. 8 - A study was performed looking at the effect of...Ch. 8 - A study was performed looking at the effect of...Ch. 8 - Prob. 81PCh. 8 - Prob. 82PCh. 8 - Prob. 83PCh. 8 - Tennis elbow is a painful condition that afflicts...Ch. 8 - Prob. 85PCh. 8 - Prob. 86PCh. 8 - Prob. 87PCh. 8 - Prob. 88PCh. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - Prob. 94PCh. 8 - Prob. 95PCh. 8 - Prob. 96PCh. 8 - Prob. 98PCh. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study is being planned to assess whether a...Ch. 8 - A study is being planned to assess whether a...Ch. 8 - Prob. 105PCh. 8 - Prob. 106PCh. 8 - Left ventricular mass (LVM) is an important risk...Ch. 8 - Left ventricular mass (LVM) is an important risk...Ch. 8 - Prob. 109PCh. 8 - Prob. 110PCh. 8 - Prob. 111PCh. 8 - A study sought to demonstrate that soy beans...Ch. 8 - Prob. 113PCh. 8 - A study sought to demonstrate that soy beans...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - The Diabetes Prevention Study was a randomized...Ch. 8 - Prob. 122PCh. 8 - Prob. 123PCh. 8 - Prob. 124PCh. 8 - Prob. 125PCh. 8 - Prob. 126PCh. 8 - Prob. 127PCh. 8 - A study looked at the influence of retirement on...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Prob. 134PCh. 8 - Prob. 135PCh. 8 - Prob. 136PCh. 8 - Prob. 137PCh. 8 - Prob. 138PCh. 8 - Prob. 142PCh. 8 - Prob. 143PCh. 8 - Prob. 144PCh. 8 - Prob. 145PCh. 8 - A study of genetic factors related to coronary...Ch. 8 - A study of genetic factors related to coronary...Ch. 8 - A study of genetic factors related to coronary...Ch. 8 - Prob. 149PCh. 8 - Prob. 150PCh. 8 - Prob. 151PCh. 8 - Prob. 152PCh. 8 - Prob. 153PCh. 8 - Prob. 154PCh. 8 - Prob. 155PCh. 8 - An individual has been exercising at a local gym...Ch. 8 - Prob. 157PCh. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - The following data are from a study on Botox...Ch. 8 - The following data are from a study on Botox...Ch. 8 - Prob. 166PCh. 8 - Prob. 167PCh. 8 - Prob. 168PCh. 8 - The EPIC-Norfolk study, a study of diet and cancer...Ch. 8 - Prob. 170PCh. 8 - Prob. 171PCh. 8 - Prob. 172PCh. 8 - Prob. 173PCh. 8 - Prob. 174PCh. 8 - Prob. 175PCh. 8 - Prob. 176P
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