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Average deviations

  1. May 25, 2005 #1
    Why is the average of the deviations of a set of measurement values always zero?
  2. jcsd
  3. May 25, 2005 #2


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    Deviations from what?
  4. May 26, 2005 #3


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    You probably mean, why is:

    [itex]\langle X-\langle X\rangle \rangle =0[/itex]

    for any distribution X. It's in the nature of the average. Use the linearity of expectations to show it.
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