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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

Ask the Professor Forum

Hi, I'm very, very confused with identifying whether an estimator is biased or unbiased. Can you explain how to identify if its biased or unbiased?

Posted to STATS 1 on Monday, August 19, 2013   Replies: 2

Professor Mcguckian
5:18 PM EST

Hi Travis,
This is a really simple idea.  If k is used to estimate A, then k is unbiased as long as the expected value of k is A.  So if E(k) = A, k is unbiased as an estimate of A.  If it were something like, E(k) = A + 6, k would be biased as an estimator of A.  


Professor McGuckian

6:39 PM EST
I can't believe how quickly this solved my problem. I was struggling with this but after reading the answer and watching the video, it became much clearer. I really appreciate this section of the website Professor. It's good to see that I am not the only one with these questions, and it's even better to see such a helpful response so quickly. Thanks again!

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