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Thread: tending to infinity of standard deviations

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    tending to infinity of standard deviations



    hi guys,

    i have a question puzzling me:

    if x tends to infinity based on some function (where x is a number) ,
    does it imply that the standard deviation of x tend to Zero ?

    cheers,
    joey

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    RotParaTon
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    Re: tending to infinity of standard deviations

    I don't understand what you're saying?

    You say "where x is a number" but then you talk about the standard deviation of x - which implies x is either a random variable or a vector of results. Can you reword what you're trying to say?

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    Re: tending to infinity of standard deviations

    hi dason,

    this is true, x is a vector with a standard deviation. It is infact a 2D coordinate position.

    So, I have :

    x = [ 20 ; 34555] +/- 255
    where 255 is the standard deviation.

    Now,I know that my vector x tends to infinity and I am getting a rather large standard deviation for it, which I think means that there is high uncertainty associated with 'x' (or at least this is what I assume ,not 100% sure on that).

    Can I make the assumption that if x tends to infinity , then its standard deviation(i.e.precision) will tend to zero?

    cheers
    Joe

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    RotParaTon
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    Re: tending to infinity of standard deviations

    Without knowing more or making additional assumptions I don't see how you could assume that.

    Also note that precision is 1/standarddeviation which might be what's causing part of my confusion with your problem. You keep saying that the standard deviation grows as x gets large and then you say that you want to make the claim that the standard deviation goes to 0 as x gets large - which contradicts what you previously said...

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    Re: tending to infinity of standard deviations

    Dason,

    I will ask something more straightforward.

    If x tend to Inf
    is it correct to imply Std_dev_of_x also tend to Inf ?

    cheers

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    Re: tending to infinity of standard deviations


    Once again... Without knowing more or making additional assumptions I don't see how you could assume that.

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