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> There is internal chaos in the game that forces the probabilistic distribution. Predicting an election based on polls is an entirely different matter. The ele

by jules 14y ago

> There is internal chaos in the game that forces the probabilistic distribution. Predicting an election based on polls is an entirely different matter. The election will turn out one way or another. If the same people voted for President 100 times without an external factor interfering differently across samples, the outcome would be the same every time. This is a distinction without a difference. There is "internal chaos" in the game because we don't know its initial conditions exactly, just like in the elections. If we had precise knowledge about the particles in the ball, the field, and the players, we could theoretically predict the outcome with high certainty. Except for quantum mechanical effects, statistics isn't about true randomness, it's about modeling lack of knowledge.

loup-vaillant 14y ago
Nitpick: even for quantum mechanical effects. The equations have no randomness in them. As far as we know, the laws of physics are deterministic. It's just that we can't know in advance which Everett branch we will subjectively experience. We could (in principle) compute what proportion of Everett branches lead to what outcome, though. Probability is still in the mind. Not in the territory. http://lesswrong.com/lw/oj/probability_is_in_the_mind/ http://lesswrong.com/lw/oj/probability_is_in_the_mind/ (In case you didn't already spot me.)
- jules 14y ago
  In a sense that's true, but Bell's inequalities show that there is something qualitatively different about quantum mechanical randomness. Bar some technicalities, they show that there isn't some hidden internal state that determines what outcome we experience, unlike with elections and baseball (assuming QM effects don't play a significant role in those). In this sense, QM is "truly random". That said, even though there is good experimental evidence for this, it is not 100% certain that the world actually works this way. http://en.wikipedia.org/wiki/Bells_theorem http://en.wikipedia.org/wiki/Bells_theorem
  - loup-vaillant 14y ago
    Nothing is 100% sure :-) http://lesswrong.com/lw/mp/0_and_1_are_not_probabilities/ http://lesswrong.com/lw/mp/0_and_1_are_not_probabilities/ But yeah, as long as we didn't find complete laws of physics, we're bound to ignore something.
    - jules 14y ago
      Not sure if you got what I'm saying...in case I didn't explain it clearly enough: Bell's inequalities show that quantum randomness CANNOT be explained by an underlying deterministic law of physics that we're ignoring. With ordinary probability you can never find out whether it's truly random or whether there is some underlying deterministic process that you just don't have knowledge about. Turns out with quantum mechanics, which works with probability amplitudes instead of just probabilities, you can rule out such an underlying deterministic process (again modulo technicalities). This is one of the most striking results of physics, and Einstein himself didn't believe it at first.
      - loup-vaillant 14y ago
        Disclaimer: I have read http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ cover to cover. Let's see with an example. A half sievered mirror, a photon going through (or bouncing), and 2 detectors. You say there is no hidden variable that would allow us to predict which detector we will see go off. I agree. It doesn't mean however that the laws of physics have true randomness in them. Under the Everett interpretation, two "worlds" (blobs of amplitude) are created: one in which detector 1 goes off, and one in which detector 2 goes off. from the outside, this is purely deterministic. The only randomness lies in our subjective experience. The only question remaining is why do we experience the Born statistics (based on square moduli), rather than something else (like, based on moduli)? We would have true randomness at the fundamental level if some form of the Copenhagen interpretation where true. But believing the blob of amplitude we don't see would mysteriously disappear, violating the equations in the process? That's just nuts. If this idea appeared after the Everett interpretation, it would have been ridiculed.
kfury 14y ago
Author here. You're right, and this was an intentional omission because it was irrelevant to my larger argument. If you want to go to the full depth of determinism then yes, with complete knowledge you can eliminate any chaotic factors in the model. The greater point though is that with our current capability of determining state we can eliminate a huge amount of chaotic factors from elections, but very, very few chaotic factors from sports and lotto drawings. We're not anywhere near the ability to determine state to that degree, and even if we were there's the certitude that unless the system was completely closed before the measurements were taken, the minute changes that result from the prediction (a team getting a sense of security, a fan cheering louder, a teammate changing a stride into the locker room because he read a tweet spawned by the prediction) throw the prediction out the window. So yes, on a scientific basis you're right and that's the grist for another blog post, but on a practical level it's irrelevant.

by jules 14y ago

loup-vaillant 14y ago

Nitpick: even for quantum mechanical effects. The equations have no randomness in them. As far as we know, the laws of physics are deterministic. It's just that we can't know in advance which Everett branch we will subjectively experience. We could (in principle) compute what proportion of Everett branches lead to what outcome, though. Probability is still in the mind. Not in the territory. http://lesswrong.com/lw/oj/probability_is_in_the_mind/ http://lesswrong.com/lw/oj/probability_is_in_the_mind/ (In case you didn't already spot me.)

jules 14y ago
In a sense that's true, but Bell's inequalities show that there is something qualitatively different about quantum mechanical randomness. Bar some technicalities, they show that there isn't some hidden internal state that determines what outcome we experience, unlike with elections and baseball (assuming QM effects don't play a significant role in those). In this sense, QM is "truly random". That said, even though there is good experimental evidence for this, it is not 100% certain that the world actually works this way. http://en.wikipedia.org/wiki/Bells_theorem http://en.wikipedia.org/wiki/Bells_theorem
- loup-vaillant 14y ago
  Nothing is 100% sure :-) http://lesswrong.com/lw/mp/0_and_1_are_not_probabilities/ http://lesswrong.com/lw/mp/0_and_1_are_not_probabilities/ But yeah, as long as we didn't find complete laws of physics, we're bound to ignore something.
  - jules 14y ago
    Not sure if you got what I'm saying...in case I didn't explain it clearly enough: Bell's inequalities show that quantum randomness CANNOT be explained by an underlying deterministic law of physics that we're ignoring. With ordinary probability you can never find out whether it's truly random or whether there is some underlying deterministic process that you just don't have knowledge about. Turns out with quantum mechanics, which works with probability amplitudes instead of just probabilities, you can rule out such an underlying deterministic process (again modulo technicalities). This is one of the most striking results of physics, and Einstein himself didn't believe it at first.
    - loup-vaillant 14y ago
      Disclaimer: I have read http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ cover to cover. Let's see with an example. A half sievered mirror, a photon going through (or bouncing), and 2 detectors. You say there is no hidden variable that would allow us to predict which detector we will see go off. I agree. It doesn't mean however that the laws of physics have true randomness in them. Under the Everett interpretation, two "worlds" (blobs of amplitude) are created: one in which detector 1 goes off, and one in which detector 2 goes off. from the outside, this is purely deterministic. The only randomness lies in our subjective experience. The only question remaining is why do we experience the Born statistics (based on square moduli), rather than something else (like, based on moduli)? We would have true randomness at the fundamental level if some form of the Copenhagen interpretation where true. But believing the blob of amplitude we don't see would mysteriously disappear, violating the equations in the process? That's just nuts. If this idea appeared after the Everett interpretation, it would have been ridiculed.

kfury 14y ago

Author here. You're right, and this was an intentional omission because it was irrelevant to my larger argument. If you want to go to the full depth of determinism then yes, with complete knowledge you can eliminate any chaotic factors in the model. The greater point though is that with our current capability of determining state we can eliminate a huge amount of chaotic factors from elections, but very, very few chaotic factors from sports and lotto drawings. We're not anywhere near the ability to determine state to that degree, and even if we were there's the certitude that unless the system was completely closed before the measurements were taken, the minute changes that result from the prediction (a team getting a sense of security, a fan cheering louder, a teammate changing a stride into the locker room because he read a tweet spawned by the prediction) throw the prediction out the window. So yes, on a scientific basis you're right and that's the grist for another blog post, but on a practical level it's irrelevant.