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Re: RandomArray from user defined distribution?

• To: mathgroup at smc.vnet.net
• Subject: [mg73365] Re: [mg73319] RandomArray from user defined distribution?
• From: darreng at wolfram.com
• Date: Wed, 14 Feb 2007 05:18:12 -0500 (EST)
• References: <200702121001.FAA14898@smc.vnet.net>

Assuming t is continuous and greater than 0, you have the pdf for a
special case of the gamma distribution.

In[1]:= <<Statistics`

In[2]:= PDF[GammaDistribution[2, 1/a], t] // InputForm

Out[2]//InputForm= (a^2*t)/E^(a*t)

Random numbers can then be generated via RandomArray of this distribution
with the desired choice of a.

Darren Glosemeyer
Wolfram Research


> I'd like to use the RandomArray to produce some data from
> what I think is a Poisson distribution in t
> P[t] = a^2 t Exp[-a*t]  where a is mean, sigma.
>
> I see one can use RandomArray to produce sample data from a
> lot of continuous distributions but the Poisson isn't among
> them (it's only available in the discrete form).
>
> I've made a bunch of crippled attempts to force my P[t] to
> put out examples but have failed. Any suggestions? Thanks.
>

• References:
  • RandomArray from user defined distribution?
    • From: rob <robIV@piovere.com>