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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

Example 122

Example 122:  In a 2007 study of different popular diets, 77 people used a modified* version of the Atkins Diet for one year.  Their mean weight change was -10.34 lbs.  Assume that the population standard deviation for all such weight changes is known to be 15.51 pounds.  Use a significance level of 0.05 to test the claim that the mean weight change is equal to zero.  Does the diet seem to be effective?  Does the mean weight change seem substantial enough to justify the diet?  What assumptions are necessary for the test we just conducted to be valid?

*The Atkins diet was modified to include higher levels of fiber and high quality complex carbohydrate.  


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