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Is Probability Real?

arameb.com

11–20 of 227 posts

Re: Is Probability Real?

#11
> The scientific method only works because the rules of the universe happen to be simple, while the set of observations it offers is vast. Kolmogorov complexity captures this defining characteristic of our reality.

I've never seen this spelled out so beautifully!

Re: Is Probability Real?

#12
post #8
post #5

Earlier quoted context omitted.

A simple sentence that I've found useful for pedagogy: "the probability of that coin toss being 50% does not talk about the coin; it talks about you , and about your partial knowledge of the universe." You can add: "The coin toss itself is deterministic and the result can be computed if you know the initial position and speed." They will inevitably bother you about the physical impossibility to measure the starting p…

> the probability of that coin toss being 50% does not talk about the coin; it talks about you, and about your partial knowledge of the universe. But it does talk about the coin - a weighted coin would have a different probability. Same in the example with the white/black balls - if they weren't 5 white and 5 black but 6 white and 4 black, the probability you would assign to the top one would be different. Again, the…

This is still a partial knowledge situation - you have the information that there are a certain proportion of colored balls in the chamber, but not the information about their order. The probability includes the information we do know and allows inferences about information we don’t know.

Re: Is Probability Real?

#13
post #8

Earlier quoted context omitted.

> the probability of that coin toss being 50% does not talk about the coin; it talks about you, and about your partial knowledge of the universe. But it does talk about the coin - a weighted coin would have a different probability. Same in the example with the white/black balls - if they weren't 5 white and 5 black but 6 white and 4 black, the probability you would assign to the top one would be different. Again, the…

This is still a partial knowledge situation - you have the information that there are a certain proportion of colored balls in the chamber, but not the information about their order. The probability includes the information we do know and allows inferences about information we don’t know.

Sure, I just can't agree with the parent statement that probability has nothing to do with the object it describes, which is demonstrably false.

Re: Is Probability Real?

#14
post #7

Earlier quoted context omitted.

How does the ball situation help? It has the same problems of physical impossibility of measuring however the balls were ordered. (Modelling someone's brain?) I guess the argument works on someone with an unscientific model of the human brain, but that's one step forward and two steps back.

Somebody just put the balls there carefully, and did not tell you in what order, just how many of each color.

That still boils down to a lack of prior information which I don't think removes the argument for "I don't have enough information."

Probably have to use actual quantum phenomena that behave probabilistically by definition if you want a currently irrefutable physical example.

I'm personally not convinced even this is fundamentally probabilistic and we currently have to rely on probability theory as a crutch for complex behaviors we just quite don't understand yet or don't have the time and resources to compute.

Re: Is Probability Real?

#16
I'm glad to see a write-up of this. I've been searching recently for a way to reasonably define probability without having to invoke either hypothetical infinitely repeated experiments or placing bets (since the latter is really just implicitly invoking the former). I'm looking forward to part 2!

Re: Is Probability Real?

#17
post #5
post #2

Since this topic isn't so well-known, I wrote the case arguing that frequentist interpretations don't work, but algorithmic information theory (Kolmogorov complexity) does. I want to make this accessible and persuasive, so thoughts, questions, and arguments would be appreciated!

A simple sentence that I've found useful for pedagogy: "the probability of that coin toss being 50% does not talk about the coin; it talks about you , and about your partial knowledge of the universe." You can add: "The coin toss itself is deterministic and the result can be computed if you know the initial position and speed." They will inevitably bother you about the physical impossibility to measure the starting p…

This is basically the Bayesian interpretation of probability.

Re: Is Probability Real?

#18
post #13

Earlier quoted context omitted.

This is still a partial knowledge situation - you have the information that there are a certain proportion of colored balls in the chamber, but not the information about their order. The probability includes the information we do know and allows inferences about information we don’t know.

Sure, I just can't agree with the parent statement that probability has nothing to do with the object it describes, which is demonstrably false.

I don't think it's demonstrably false: If you don't know that the coin is weighted, the probability is 50%. Probabilities are predictions and estimates, not fundamentally about the thing itself, but about what we know about the thing.

Re: Is Probability Real?

#20
post #17
post #5

Earlier quoted context omitted.

A simple sentence that I've found useful for pedagogy: "the probability of that coin toss being 50% does not talk about the coin; it talks about you , and about your partial knowledge of the universe." You can add: "The coin toss itself is deterministic and the result can be computed if you know the initial position and speed." They will inevitably bother you about the physical impossibility to measure the starting p…

This is basically the Bayesian interpretation of probability.

Of course. But if you pronounce a fancy word like "bayesian" there's a large amount of minds that shut irremediably.
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