Results 1 to 3 of 3

Thread: How do I get this approximation?

  1. #1
    Member
    Joined
    May 2008
    Posts
    142

    How do I get this approximation?

    I'm struggling to get the approximation

    How do I get this approximation?-screen-shot-2018-12-12-15.09.30.png

    when after N steps in a random walk the mean=N/6 and variance=N/18. I know that as N becomes very large, we can approximate it to a Normal distribution, but my algebra leaves me this

    How do I get this approximation?-screen-shot-2018-12-12-15.13.13.png

    Any ideas?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2013
    From
    California
    Posts
    6,542
    Thanks
    2882

    Re: How do I get this approximation?

    it would be nice to know what that is approximating.

    If it's a normal distribution with the given mean and variance then the N in the numerator of the argument to the exponential function should be N/2
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    May 2008
    Posts
    142

    Re: How do I get this approximation?

    Apologies.

    I'm trying to show that

    How do I get this approximation?-screen-shot-2018-12-12-16.25.09.png

    using the values for the mean=N*<r>=N/6 and variance=N*Var(r)=N/18 that I mentioned above.
    Last edited by Cairo; Dec 12th 2018 at 07:34 AM.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Approximation of 1/(2+x)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Dec 6th 2013, 11:48 AM
  2. Approximation
    Posted in the Calculus Forum
    Replies: 6
    Last Post: Aug 30th 2011, 05:08 AM
  3. Approximation
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Aug 25th 2011, 04:31 AM
  4. Best approximation
    Posted in the Differential Geometry Forum
    Replies: 1
    Last Post: Nov 2nd 2009, 03:14 AM
  5. approximation
    Posted in the Algebra Forum
    Replies: 2
    Last Post: Sep 5th 2009, 04:46 AM

/mathhelpforum @mathhelpforum