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Power equation

  1. Apr 26, 2012 #1
    In the following equation:

    c = sum_i( ( p(i)^a ) * b(i) ) / sum_i( p(i)^a )

    "c", "0 <= p(i) < 1" and "b(i)" are known.
    How do I calculate "a"?
    Last edited: Apr 26, 2012
  2. jcsd
  3. Apr 26, 2012 #2

    It's really hard to understand what you really meant without LaTeX, but if you meant

    [itex]\displaystyle{c=\frac{\sum p_i^a b_i}{\sum p_i^a}\Longrightarrow \sum p_i^a(c-b_i)=0}[/itex] ...and this is as far as I can go without any further data.

  4. Apr 26, 2012 #3
    That is correct, I totally agree. The only further data is that "b(i)", "0 <= p(i) < 1" and "c" are known. I was hoping to be able to calculate "a" ... analytically.
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