Re: Random Number Generation Dialog Box

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From: JE McGimpsey (jemcgimpsey_at_mvps.org)
Date: 04/18/04 

Date: Sun, 18 Apr 2004 17:57:45 -0600

In article <BCA84345.3CF2C%plasticnitlion@wrappermindspring.com>,
 Bob Harris <plasticnitlion@wrappermindspring.com> wrote:

> Am using Excel 2001 and want to generate some random numbers from a normal
> distribution. A help search tells me about what looks like a wonder dialog
> box that will do what I want. But it does not tell me how to get to that
> dialog box. I've hunted through menu after menu trying to locate it.
> Anyone know where it is?
>
> What's the use of having the function in help if they don't tell you how to
> get to it?

Well, XL2001's Help, while miles ahead of XL5's and somewhat better than
XL98, was still very much a work in progress. Later versions of XL let
you know that the Random Number Generator Dialog Box is part of the
Analysis Toolpak Add-in (Tools/Add-ins..., check the appropriate
checkbox). Once the ATP is loaded, you can access the RNGDB using
Tools/Data Analysis/Random Number Generation.

Be aware, however, that the ATP's pseudorandom number generator is not
really up to speed statistically. It's probably good enough for casual
use, but for truly serious work, it just plain sucks. XL01's RAND()
function is a bit better, and if you search the Excel archives:

    http://groups.google.com/advanced_group_search?q=group:*excel*

you can find posts by David Braden, among others that describe how to
retrieve normally distributed random numbers from RAND(). RAND() is
still not great for XL versions prior to WinXL03 (as patched - the
unpatched version returns negative numbers after a while), including
MacXLv.X. I have high hopes, however, for XL2004, which will be released
shortly.

Relevant Pages

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