Compression of random binary data

[Ben Bacarisse]

Steve D'Aprano <steve+python at pearwood.info> writes:

> On Fri, 27 Oct 2017 09:53 am, Ben Bacarisse wrote:
>
>> A source of random can be defined but "random data" is much more
>> illusive.
>
> Random data = any set of data generated by "a source of random".

(I had an editing error there; it should be "a source of random data".)

Yes, that's a fine definition, but it has the disadvantage of not being
a verifiable property of the thing defined -- you can't know, from the
data themselves, if they constitute random data.  You would not care
about a compression program that worked on some data that looks random,
you'd want to present your own data for compression (and then you can
use a random source with confidence because the data are yours).  That's
the big win (for me) of talking about "arbitrary data".

-- 
Ben.