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Random variable x

  1. Nov 26, 2009 #1
    Hi if someone can please help me to this question???? PLease?
    Thank you
    maria
    http://img21.imageshack.us/img21/9793/statistikh4.jpg [Broken]
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Nov 26, 2009 #2

    mathman

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    Re: Unbiased

    Please define S!!!
     
  4. Nov 30, 2009 #3
    Re: Unbiased

    Sorry i forgot to mention what S is. Here:
    http://img682.imageshack.us/img682/3866/question4.jpg [Broken]
    i have done part (i) but i can't do part (ii)
    Can you please help??
    Thank you
    Maria
     
    Last edited by a moderator: May 4, 2017
  5. Nov 30, 2009 #4

    mathman

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    Re: Unbiased

    V(S)=E(S2)-E(S)2
    E(S2)=σ2
    V(S) must be > 0, otherwise S would not be random.
    Therefore E(S) must be < σ.
     
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