Re: Random numbers from random numbers... Re: [question] On the topicof

[Kevin Shea <kev@d-cubed.co.uk>]

My contribution on this one:

If you're using a computer to generate pseudo-random numbers, the best
you'll get is using the output of time() for srand() and using rand().
rand simply produces a fixed sequence of values starting from the seed.
Fancy srand() procedures only start you at a different point of the
sequence, but don't change the "randomness", ie distribution of the
numbers.

What you *can* improve is using a better generator function. An example
is random() which often exists on Unixes. This has a bigger period and
the lower bits are better behaved as well (the lower bits of rand() are
not well distributed). I think there's also a Gnu package somewhere
that will produce random numbers based on various probability
distribution
to save you that work as well.

If you *really* want something different, buy a copy of some statistical
tables from any academic bookshop which will have random number tables
in
the back for various probability distributions.

The statistics tables will also give you exact details of any
probability
distribution you're interested in.

What exactly do you mean by "predictability" of your random numbers? You
don't seem to mean what probability distribution the follow, but instead
you seem to be trying to actually predict the next number that comes up?
Have a look for the Gambler's Fallacy if that's what you're trying to
do :]. More info?

Hope this helps.

Kev
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