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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

CI for Matched Pairs

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
 

 

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