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Math Help - Probability question

  1. #1
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    Probability question

    Hey,

    Could I get a simple explanation for the equation below?

    p(x)=lim n0
    n->oo n

    Thanks.
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  2. #2
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    Quote Originally Posted by SeanC View Post
    Could I get a simple explanation for the equation below?
    p(x)=lim n0
    n->oo n
    There is a very easy explication: as written it is mealingless.
    What is the context of the question?
    What are the definitions of the terms involved?
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  3. #3
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    Quote Originally Posted by Plato View Post
    There is a very easy explication: as written it is mealingless.
    What is the context of the question?
    What are the definitions of the terms involved?
    Ah, sorry. If n trials of an experiment are run and produce n0 occurrences of x, the probably p of x is...(the equation).

    I guess the only parts I don't quite understand are the LIM part and the n0 (why is there a 0...to distinguish it from "n"?).

    I apologize if this sounds retarded, but it's been years since I even looked at an algebraic or calculus equation and I now have a need for it...
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  4. #4
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    Quote Originally Posted by SeanC View Post
    Hey,

    Could I get a simple explanation for the equation below?

    p(x)=lim n0
    n->oo n

    Thanks.
    It is the standard frequentist definition of probability of outcome x. If you
    repeat the experiment a large number n of times, and record n_0 occurences
    of out come x we estimate the probability of x as:

     <br />
\hat{p}(x) = \frac{n_0}{n}<br />

    Then the definition of the probability of x is the limit of such an estimator as n \to \infty.


    This can be written as:

    <br />
p(x)=\lim_{n \to \infty} \frac{n_0}{n}<br />

    but this is a abuse of notation from other parts of mathematics as this limit
    is not the usual limit encountered in other parts of mathematics, and cannot
    be evaluated.

    (Just learn it, you will need it for your exam, but it is nonsense. There are
    better defintions that you will encounter if you contine with the study of
    probability)

    RonL
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  5. #5
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    Quote Originally Posted by CaptainBlack View Post
    It is the standard frequentist definition of probability of outcome x. If you
    repeat the experiment a large number n of times, and record n_0 occurences
    of out come x we estimate the probability of x as:

     <br />
\hat{p}(x) = \frac{n_0}{n}<br />

    Then the definition of the probability of x is the limit of such an estimator as n \to \infty.


    This can be written as:

    <br />
p(x)=\lim_{n \to \infty} \frac{n_0}{n}<br />

    but this is a abuse of notation from other parts of mathematics as this limit
    is not the usual limit encountered in other parts of mathematics, and cannot
    be evaluated.

    (Just learn it, you will need it for your exam, but it is nonsense. There are
    better defintions that you will encounter if you contine with the study of
    probability)

    RonL
    Great, thank you.
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