Truly random?

[Thad Smith]

The ideal solution (which, however, requires an internet connection) is to
connect to www.random.org and download some random bytes...

They are truly random, since they come from *sampling backgound noise in the
atmosphere* (how cool is that?!).

Practically speaking, a reasonable PRNG would be more suitable. If you
needed secrecy (such as for high-stakes gambling), you wouldn't want to
connect to an external source with a non-secure connection, and even if
you secured the pipe, you would need reasonable assurances that the data
wasn't leaked (intentionally or otherwise) on the other end.

 

[lawrence.jones]

And it is marginally on-topic, because the code of a PRNG with IIRC
characteristics like those you describe appears in the text of the C
standard.

No, the code in the standard generates a result whose low-order bits are
just as random as the high-order bits (its internal state has 16 more
bits than its return values).

-Larry Jones

Why is it you always rip your pants on the day everyone has to
demonstrate a math problem at the chalkboard? -- Calvin

 

[Jordan Abel]

No, the code in the standard generates a result whose low-order bits are
just as random as the high-order bits (its internal state has 16 more
bits than its return values).

IIRC even though the shifting makes the low-order bits sufficiently
random to be useful, the higher ones are even more random - i.e. the
"randomness" [specifically, the length of the repeat period] is a
continuously increasing function as you go from lower to higher bits.

I don't know much about this, this is just how it was explained to me.

 

[Tim Rentsch]

No, the code in the standard generates a result whose low-order bits are
just as random as the high-order bits (its internal state has 16 more
bits than its return values).

My tests [*] show the low-order bits to be significantly less
random than the high-order bits.

[*] Based on a version of the simplified poker test given in
Knuth volume 2.