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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
Lecture Examples
Example 145 Randy Stinchfield of the University of Minnesota studied the gambling activities of public school students in 1992 and 1998 (Journal of Gambling Studies, Winter 2001). His results are reported below. Form a 99% confidence interval to estimate the true difference between the proportion of public school students who gambled in 1992 and 1998. Does there seem to be a difference?
1992 
1998 

Survey n 
21,484 
23,199 
Number who gambled 
4,684 
5,313 
Proportion who gambled 
.218 
.229 