4 ms·

Essentially all economic models of investment have a time dimension. I'm not sure where you're getting the idea that it's left out. Also, the field has gone f

Essentially all economic models of investment have a time dimension. I'm not sure where you're getting the idea that it's left out. Also, the field has gone far beyond von Neumann-Morganstern, so I'm not sure where you're getting that, either. I'm simply making the point that expected utility does not require ergodicity. If you read the proofs, it's clear. If you don't want to read the proofs, the best that I can do is provide indirect historical evidence.

ReflectedImage 6y ago
"I'm simply making the point that expected utility does not require ergodicity." Okay well that point is wrong, as in very wrong. Ergodicity can be directly defined as it is valid to take the Expected Value. That's just what Ergodicity means. Expected Utility is defined on top of Expected Value. So Expected Utility assumes Ergodicity.
QuesnayJr 6y ago
Weird, I can't reply directly. Peters (and you, I assume) are taking a strong philosophical stance on the meaning of probability. Lots of people would disagree with you. Essentially all Bayesians would disagree with you, for example.
- ReflectedImage 6y ago
  Yeah reply seems to be a bit buggy. "strong philosophical stance on the meaning of probability" ??? It's taken directly from thermodynamics: https://en.wikipedia.org/wiki/Ergodic_hypothesis https://en.wikipedia.org/wiki/Ergodic_hypothesis You would be arguing directly with the laws of thermodynamics.
  - QuesnayJr 6y ago
    This is what I've always suspected was the subtext of this. "We're physicists, and what we learned while thinking about microcanonical ensemble is all you need to know about probability. No, we have nothing to learn from the hundreds of probabilists and statisticians on the subject of probability, or the hundred-year old debate on the meaning of probability." There are more things in heaven and earth than dreamt of in your philosophy, Horatio: https://plato.stanford.edu/entries/probability-interpret/ https://plato.stanford.edu/entries/probability-interpret/
    - kgwgk 6y ago
      There are a thing or two that they could learn from other physicists as well. https://bayes.wustl.edu/etj/articles/theory.1.pdf https://bayes.wustl.edu/etj/articles/theory.1.pdf “It is concluded that statistical mechanics need not be regarded as a physical theory dependent for its validity on the truth of additional assumptions not contained in the laws of mechanics (such as ergodicity, metric transitivity, equal a priori probabilities, etc.).”

ReflectedImage 6y ago

"I'm simply making the point that expected utility does not require ergodicity." Okay well that point is wrong, as in very wrong. Ergodicity can be directly defined as it is valid to take the Expected Value. That's just what Ergodicity means. Expected Utility is defined on top of Expected Value. So Expected Utility assumes Ergodicity.

QuesnayJr 6y ago

Weird, I can't reply directly. Peters (and you, I assume) are taking a strong philosophical stance on the meaning of probability. Lots of people would disagree with you. Essentially all Bayesians would disagree with you, for example.

ReflectedImage 6y ago
Yeah reply seems to be a bit buggy. "strong philosophical stance on the meaning of probability" ??? It's taken directly from thermodynamics: https://en.wikipedia.org/wiki/Ergodic_hypothesis https://en.wikipedia.org/wiki/Ergodic_hypothesis You would be arguing directly with the laws of thermodynamics.
- QuesnayJr 6y ago
  This is what I've always suspected was the subtext of this. "We're physicists, and what we learned while thinking about microcanonical ensemble is all you need to know about probability. No, we have nothing to learn from the hundreds of probabilists and statisticians on the subject of probability, or the hundred-year old debate on the meaning of probability." There are more things in heaven and earth than dreamt of in your philosophy, Horatio: https://plato.stanford.edu/entries/probability-interpret/ https://plato.stanford.edu/entries/probability-interpret/
  - kgwgk 6y ago
    There are a thing or two that they could learn from other physicists as well. https://bayes.wustl.edu/etj/articles/theory.1.pdf https://bayes.wustl.edu/etj/articles/theory.1.pdf “It is concluded that statistical mechanics need not be regarded as a physical theory dependent for its validity on the truth of additional assumptions not contained in the laws of mechanics (such as ergodicity, metric transitivity, equal a priori probabilities, etc.).”