3 ms·
What you're describing is not randomness, it's independence. It's hard to define randomness. I think non-determinism is better than your definition.
by elcomet 5y ago
What you're describing is not randomness, it's independence.
It's hard to define randomness. I think non-determinism is better than your definition.
- mjburgess 5y agoIt isn't hard to define randomness. It's an epistemic condition on the knowability of Y given X. Non-determinism is an incoherent definition of randomness; classical physical processes are entirely deterministic. The point of a coinflip being random is that it is random with respect to the information both observers of the coinflip have. It isnt random with respect to /any/ piece of information. There are almost no processes which are non-deterministic in this sense. Not enough to bother calling them random; and in physics we do not: the word is indeterminate. Randomness has nothing to do with quantum mechanics; it wasn't invented in the 1920s. It's an epistemic condition. The RANDOM variable X, st. X ~ N(mean, std) provides a random number x -- x isnt random with repect to the outcome which produced x; nor is it random with respect to an index of a vector in which it is contained.
- elcomet 5y agoThis does not match the intuitive notion of randomness though. I would say for a given variable to be random, it must not be predictible, given any other variables that humans can know. I don't think it makes sense to say that X is random "with respect to Y", that's just the definition of independence. And a constant variable is independent from all other variables, but it's definitely not random.
- mjburgess 5y agoThen only quantum indeterminate phenomenon is random, and nothing else. I dont think many people have thought enough about the world to appeal to their intuitions. Randomness isnt quantum indeterminacy.