[OT] Compression of random binary data

[Tim Delaney]

On 14 July 2016 at 05:35, Marko Rauhamaa <marko at pacujo.net> wrote:

> Michael Torrie <torriem at gmail.com>:
> > If the data is truly random then it does not matter whether you have 5
> > bytes or 5 GB. There is no pattern to discern, and having more chunks
> > of random data won't make it possible to compress.
>
> That's true if "truly random" means "evenly distributed". You might have
> genuine random numbers with some other distribution, for example
> Gaussian: <URL: https://www.random.org/gaussian-distributions/>. Such
> sequences of random numbers may well be compressible.
>

No one is saying that *all* random data is incompressible - in fact, some
random samples are *very* compressible. A single sample of random data
might look very much like the text of "A Midsummer Night's Dream"
(especially if your method of choosing the random sample was to pick a book
off a library shelf).

But unless otherwise qualified, a claim of being able to compress random
data is taken to mean any and all sets of random data.

Anyway, that's going to be my only contribution to this thread.

Tim Delaney