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Homework Help: Need help understanding how to interpret a statistics problem

  1. Sep 24, 2011 #1
    1. The problem statement, all variables and given/known data
    Let c be a constant, and define [tex]Y_{i}=1[/tex] if [tex]X_{i}\leq[/tex] c and zero otherwise. Find a statistic that is a function of [tex]Y_{1},Y_{2},...Y_{n}[/tex] and also unbiased for [tex]F_{X}(c)=\Phi\left(\dfrac{c-\mu}{\sigma}\right).[/tex]

    2. Relevant equations

    3. The attempt at a solution
    not even sure how to being. i want some function of y_1,...,y_n, call it a, such that E(a)=phi((c-mu)/sigma)... but, yeah... i have no idea where to begin.

    also, sorry for my crappy latex
  2. jcsd
  3. Sep 24, 2011 #2
    oh, i left out that X_i are distributed from a N(mu,sigma), and U=SUM(X_i) and W=SUM(X_i^2), if that matters.
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