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From: "John D'Errico" <woodchips@rochester.rr.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Limiting case of an exponential distribution
Date: Sat, 10 Jan 2009 14:23:01 +0000 (UTC)
Organization: John D'Errico (1-3LEW5R)
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Adshak <adshaikh.hipnet@googlemail.com> wrote in message <5e3bfffd-9cf6-417e-8c92-fe40feedcd71@o40g2000prn.googlegroups.com>...
> Dear All,
> 
> I have an exponential distribution curve which is given by:
> 
> t = (0.0001:0.0001:15);
> z = (15625000/567) .*t.^9.*exp(-10.*t);
> 
> figure;
> plot(t,z);
> 
> 
> Now I am told that the limiting case of this exponential distribution
> is a gaussian curve.
> 
> I am not very good at statistics.
> 
> Can somebody kindly explain to me the significane of the limiting case
> of this exponential curve and why it is a gaussian curve....and how do
> I find anf fit this gaussian curve to this exponential curve (a few
> matlab commands might very helpful).
> 
> I have tried googling 'limiting case of exponential distribution' but
> didnt find any good explanation.
> 
> Thanks in advance.

Perhaps the problem is this is not an exponential
distribution at all. Assuming that you are trying to
plot the pdf, this is a:

http://en.wikipedia.org/wiki/Gamma_distribution

If you wish to approximate this with a normal
distribution, then you could most simply just
use a normal with the same mean and variance
as this gamma.

John