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sidww2 | 11 years ago

What? The modern definition of pseudorandomness (https://en.wikipedia.org/wiki/Pseudorandomness#Pseudorandomn...) was figured out in the 80s through the works of Blum, Goldwasser, Micali, Goldreich, etc. and is not hand-wavy at all. It's pretty rigorous and reliable.

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antics|11 years ago

You are 100% mistaken that this implies we had a good definition of random sequences before Knuth. In the article you link, they discuss the uniform distribution, but any distribution (and the modern notion of probability in general) absolutely depends on a mathematically precise notion of random sequences.

If you don't believe me, read the chapter. Early probability theorists (e.g., von Mises, Kolmogorov) literally started thinking about randomness in order to define probability.

EDIT: And, I don't suppose it's worth pointing out that pseudorandomness is not at all the same thing as randomness. The fact that you seem to use them interchangeably is not a good sign IMHO.

EDIT 2: Why the unexplained downvote, HN? :(

sidww2|11 years ago

I skimmed through the extract presented (didn't have time to go into detail) but I don't see a formal definition of any kind presented in the extract. Could you point me to where it is? And if it's not in the extract, then could you quote it here?

Pseudorandomness is not the same thing as randomness but most algorithms today work on pseudorandom numbers so the concept is important. My impression was that that's what you were referring to.

PS :- FYI I didn't downvote your comment. Actually upvoted as your post made me discover some new math (various notions of randomness by kolmogorov, von mises, martin-lof) :)