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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 104: In sociology, a social network is defined as the people you make frequent contact with. The personal network size for each adult in a sample of 2,819 adults was calculated. The sample had a mean personal network size of 14.6 with a known population standard deviation of 9.8.

a. Give a point estimate for the mean personal network size of all adults

b. Form a 95% confidence interval for the mean personal network size of all adults

c. Give the practical interpretation of the interval created in part b.

d. Give the conditions required for the interval to be valid (answer: The sample must be random and n should be large, ). !!!Important!!!