Mueen Nawaz wrote:
> 	What's a "truly random" sequence?

This is a well-defined concept.  It means that (basically) the probability 
of you being able to predict the next item in the sequence is unchanged by 
any knowledge you might have.

> 	I think I know what you mean, because I used to think the same, but
> that's just my bias - I don't think there's any mathematical backing.

That's what I'm saying - I think there is.

> rather, the "truly random" is just yet another distribution  like the
> Gaussian, etc.

No, you can have any distribution you want and not be random. You can have 
any distribution you want and be random, too. Random is about predictability 
with better-than-the-distribution-suggests accuracy.

If I say "the first two characters my generator output were 'th'", you'd 
have no idea what the third letter is if it's random, but a pretty good idea 
what it might be if I said "it's an english sentence."  That sort of 
predictability.

No matter what you know, and no matter how often you've rolled the dice, 
you're not going to guess the next side with >1/6 probability (assuming 
perfect dice, of course). Any computer PRNG dice rolling can be easily 
predicted simply by looking at the PRNG and doing the math.

> 	(And be careful when you say Normal. The distribution called "normal"
> in probability is the Gaussian distribution, which I think is not what
> you meant).

I meant what are called "normal numbers" in math, not normal statistical 
distributions. Check wikipedia.

-- 
   Darren New, San Diego CA, USA (PST)
   There's no CD like OCD, there's no CD I knoooow!

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