Assignment:
Assume that the paired sample data are simple random samples and that the differences have a distribution that is approximately normal.
Confidence Interval for BMI Changes Use the same paired data from shown below to construct a 95% confidence interval estimate of the change in BMI during freshman year. Does the confidence interval include 0, and what does that suggest about BMI during freshman year?
Exercise
Does BMI Change During Freshman Year? Listed below are body mass indices (BMI) of the same students included in Table on page 489. The BMI of each student was measured in September and April of the freshman year (based on data from "Changes in Body Weight and Fat Mass of Men and Women in the First Year of College: A Study of the ‘Freshman 15'," by Hoffman, Policastro, Quick, and Lee, Journal of American College Health, Vol. 55, No. 1). Use a 0.05 significance level to test the claim that the mean change in BMI for all students is equal to 0. Does BMI appear to change during freshman year?
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April BMI
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20.15
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19.24
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20.77
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23.85
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21.32
|
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September BMI
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20.68
|
19.48
|
19.59
|
24.57
|
20.96
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