Comment by lamp_book | Hacker News Reader

Comment by lamp_book | Hacker News Reader

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From the actual journal article:

> Two additional complications arise because plasma fusion apparatuses are experimental and one-of-a-kind. First, the goodness metric for plasma is not fully established and objective: some amount of human judgement is required to assess an experiment. Second, the boundaries of safe operation are not fully understood: it would be easy for a fully-automated optimisation algorithm to propose settings that would damage the apparatus and set back progress by weeks or months.

> To increase the speed of learning and optimisation of plasma, we developed the Optometrist Algorithm. Just as in a visit to an optometrist, the algorithm offers a pair of choices to a human, and asks which one is preferable. Given the choice, the algorithm proceeds to offer another choice. While an optometrist asks a patient to choose between lens prescriptions based on clarity, our algorithm asks a human expert to choose between plasma settings based on experimental outcomes. The Optometrist Algorithm attempts to optimise a hidden utility model that the human experts may not be able to express explicitly.

I haven't read the full article nor do I understand the problem space, but the novelty seems overstated based on this. Maybe they can eventually collect metadata to automate the human intuition.

Edit: here's their formal description of it: https://www.nature.com/articles/s41598-017-06645-7/figures/2

I mean, if it has not been done before, it doesn't look like they're overstating the novelty. Most algorithms look "obvious" in hindsight :).

It's a well-known technique in the out-of-fashion world of knowledge-based systems: To create an expert system, your experts often won't be able to articulate their utility function, so you extract it by presenting them A/B choices.

Doing an old thing on a new problem counts as novel.

Sure. Just pointing out that this isn't a "new algorithm that only looks obvious because of hindsight". There's an almost endless supply of problems, like this one, that benefit from automating the assessment task of human experts.

Hot or not, but for dynamical systems optimization.

Each plasma out come is shown to a researcher as a Tinder profile, if they select the ones they want by swiping right :-)

i also haven't read the full article. I wondered if it was worth reading before i clicked the link really. How did they determine it whould be faster than.. what? doing it without computers? And if it cuts down months worth of computation to just some hours, can i expect a working fusion reactor in the next 1-2 years instead of 10-30? How did this become HN #1?

In software jargon, this is called a "Wizard" (i.e. installer wizard, calibration wizard, etc. that guide you through a process that is more complicated by asking a series of simple questions) and is an idea that dates back decades.

If I'm understanding this right, I'm pretty sure this is not in fact just a wizard. It's using people's answers to "which of these is better" to learn an objective function that can later be used for optimization. A wizard is just presenting explicit choices. Making one requires knowing all the possible paths and results in advance. You could I suppose have an "implicit wizard", where every choice was in terms of "Which of these two examples do you prefer?" rather than explicitly stating what the user was choosing between, but that would ultimately just be a more confusing version of an explicit wizard -- it would still require you to program in all the possible paths and results in advance. That's much less interesting than this.

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