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▲ amluto 4 hours ago

I’ve been contemplating this situation. I think that what the author wants out of a Jev-like model is not at all what I want out of it.

> I decided to check this on questions where the answer is well understood. For example:

> A classical particle of mass m is embedded in a system at thermodynamic equilibrium with temperature T. What is its velocity v?

If I feed that into a model, the answer I want is: “the combination of the model and the provided state has nothing useful to add to your prior”.

If I want to know the Maxwell-Boltzmann distribution, I can look it up or I can derive it or I can ask a fancy LLM to do it for me (at the cost of some reasoning tokens and some time - unless I’m using an ultraspeed inference system, I’m not getting this answer in 50ms). [0]

Similarly, if I want to know that 73% of incoming customer support requests are spam/fraud, I should measure that - it’s a property of my system, it takes some manual classification and a database query, and it will be a different percentage than your customer support system would see. I neither expect nor want my classifier to know this (unless I’m using a conventional classifier manually trained on my data, and the whole point of Jev is to avoid this).

What I want out of a system like Jev is to tell me how the probabilities change as a result of the per-sample data I provide. Which, is the case of this Boltzmann distribution question, is nothing: I provided no data and the classifier can infer nothing.

[0] A really good answer would observe that the answer depends on the dimension of the system (probably 3, but 2D systems are a thing) and also on whether the particles are hot enough for relativistic effects to matter (probably not). And maybe a good answer would check whether the material is a gas - the answer for a solid is not the same, but I suppose that’s not classical. Oh, and one shouldn’t forget drift: if you have a classical particle in a moving fluid or a classical charged particle in an electric field, you will again get a different answer.

Yes, I’m being pedantic. But if you want good answers you should be pedantic, and the Jev-like model is not where the pedantry should go.

▲charcircuit 2 hours ago | parent [-]

The point of the theoretical problems is that they should be the easiest cases to handle. How can you trust the probabilities from real world classifiers if it can't even handle well defined problems.

▲amluto 21 minutes ago | parent | next [-]

Two reasons:

1. It’s ridiculous. Not only is the question prima facie absurd for a model of this type, it sort of doesn’t fit into the whole training model. An LLM (charitably) predicts token probabilities, which one might generalize to mean that the LLM operates on probability distributions over strings. So asking for the probability of “fraud” versus “not fraud” makes sense. But asking for the probability of “1.23” versus “2.7” is kind of out of distribution - those are numbers, no one is training on an entire continuum of two-decimal-place real numbers, and similar numbers can have wildly different representations (“25.4” vs “25.40” vs “2.54e1”).

2. It’s barely a classification problem as written. If I wanted it to be a classification problem, maybe I would try:

“There is a machine that receives little sealed containers of air. In each container one molecule is painted red. The machine measured the interior temperature of one particular container and determined that it was 300K.” Question: in what range was the velocity of the red molecule at the instant that the container entered the machine. Choices: 0-100m/s, 100-200m/s, etc.

I maintain that this question is a weird thing to train a Jev-like model on and that I really feel that a classifier I use would need to answer it well.

I do find it disappointing that Jev conflates “the probabilities are all equal” with “I have no clue”, and I think it would be better if it were at least clearly documented how the model’s ability to figure something out relates to the API response probability.

▲jhayward an hour ago | parent | prev [-]

I think this comment misunderstands the nature of a probabilistic system. It doesn't reason, or use constraints, or do analytic math. It measures probabilities based on observations.

The well-defined problems aren't well-defined in this sense.