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Course Documents
Chapter 1 - Intro
Chapter 2 - Methods for Describing Sets of Data
Chapter 3 - Probability
Chapter 4 - Discrete Random Variables
Chapter 5 - Normal Random Variables
Chapter 6 - Sampling Distributions
Chapter 7 - Confidence Intervals
Chapter 8 - Tests of Hypothesis: One Sample
Chapter 9 - Confidence Intervals and Hypothesis Tests: Two Samples
Sample Exam I: Chapters 1 & 2
Sample Exam II: Chapters 3 & 4
Sample Exam III: Chapters 5 & 6
Sample Exam IV: Chapters 7 & 8
9.8 Confidence Interval to Compare Two Population Means: Matched-Pair Experiments
A strength training program is designed to improve core strength. To test its effectiveness, 12 patients are timed in seconds while holding a position called the plank before and after a 3 week strength program. Use the data below to construct a 95% confidence interval for the true μd between pre-core strength and post-core strength. Is zero in the interval? If so, what does this tell us?
Pre-Program 38 47 63 50 41 30 35 34 44 43 46 52
Post-program 67 92 120 75 69 60 68 65 131 122 120 135