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Homework Help: Statistics Definitions

  1. Apr 22, 2012 #1
    1. The problem statement, all variables and given/known data
    Let X1,…,Xn denote a random sample from a population with mean μ and variance σ^2. Assume that both μ and σ^2 are finite but unknown. Let X denote the sample mean and S^2 denote the sample variance. Are the following statements true or false?
    A-There is no difference between X and μ - the two are different notations for the same quantity.
    B- There is no difference between S^2 and σ^2 - the two are different notations for the same quantity.
    C- X is an unbiased estimator for μ.
    D- The standard error of X is σ/(sqrt n) which can be estimated as S/sqrt(n).

    2. Relevant equations

    3. The attempt at a solution
    I believe I have the right answers I just want to double check
    A- yes
    B- yes
    C- yes
    D- no
  2. jcsd
  3. Apr 22, 2012 #2


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    Science Advisor

    Actually, as I understood, a),b) are false. If they were equal, confidence intervals would not be necessary. For c),d) , there are actual formulas, so that you can verify.
  4. Apr 22, 2012 #3
    Thank you!
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