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Expectations (over variables and conditional) Watch

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    Say we have Ex(f)
    Where f is a function of random variables
    I'm not too sure what the subscript X means.

    If f only contains x, say f=1/X
    Is Ex(1/X) the same as E(1/X)?

    What about Ex(Z)?
    OR Ex(ZX)?

    Similarly for conditional expectations:
    Is E(f(X)|X) the same as E(f(X))
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    (Original post by DQd)
    Say we have Ex(f)
    Where f is a function of random variables
    I'm not too sure what the subscript X means.

    If f only contains x, say f=1/X
    Is Ex(1/X) the same as E(1/X)?

    What about Ex(Z)?
    OR Ex(ZX)?

    Similarly for conditional expectations:
    Is E(f(X)|X) the same as E(f(X))
    The one thing I would say is that subscripts should usually be defined in a self contained way, I.e. Wherever you have seen Esubscriptx, it should have been defined somewhere most likely in your notes.
 
 
 
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