> The superconducting-like behavior in LK-99 most likely originates from a magnitude reduction in resistivity caused by the first-order structural phase transition of Cu2S. [...] It is important to note that this first-order structural transition differs significantly from the second-order superconducting transition.
This seems to be about easier classification tasks with not too many samples, for which TF-IDF also works well (Table 3). But more generally gzip for text modeling might make sense. Quoting http://bactra.org/notebooks/nn-attention-and-transformers.ht... :
> Once we have a source-coding scheme, we can "invert" it to get conditional probabilities; we could even sample from it to get a generator. (We'd need a little footwork to deal with some technicalities, but not a heck of a lot.) So something I'd really love to see done, by someone with the resources, is the following experiment:
> - Code up an implementation of Lempel-Ziv without the limitations built in to (e.g.) gzip; give it as much internal memory to build its dictionary as a large language model gets to store its parameter matrix. Call this "LLZ", for "large Lempel-Ziv".
> - Feed LLZ the same corpus of texts used to fit your favorite large language model. Let it build its dictionary from that. (This needs one pass through the corpus...)
> - Build the generator from the trained LLZ.
> - Swap in this generator for the neural network in a chatbot or similar. Call this horrible thing GLLZ.
> In terms of perplexity, GLLZ will be comparable to the neural network, because Lempel-Ziv does, in fact, do universal source coding.
Maybe someone on HN will have resources for such an experiment?
Content aside, this is terrible editing on BBC’s part:
> However, the regulator hit back, saying: "It is the CMA's job to do what is best for the people, businesses and economy of the UK, not merging firms with commercial interests."
> But the Competition and Markets Authority (CMA) said its job was not to serve the interests of merging firms.
No. I was referring to the "standard concentration bound" in that paper, which applies when you have separate validation and test sets. I think the argument can usually be improved by applying small-variance inequalities such as Bernstein's, to excess risk-like quantities such as l(f_hat(x), y) - l(f_ref(x), y), to show that accuracy difference / relative rank enjoys better guarantees. For ImageNet we can use the 01 loss and set f_{ref} to a SoTA classifier which, while having its loss bounded away from 0, is "mostly similar" to most f_hat's, and thus leads to a small excess risk.
The CIFAR experiments I mentioned were https://arxiv.org/pdf/1806.00451.pdf. It doesn't contain this argument (unfortunate wording) but appears to support it well.
If you only care about identically distributed test data, test set overfitting doesn't happen that fast: if you evaluate M models on N test samples, the overfitting error is on the order of sqrt(log M / N). And even as this error becomes more noticeable, the relative ranks among the models are even more stable, as you can apply the small variance bounds. This is actually verified on models proposed for CIFAR-10.
The equation example is artificial. In practice there will be no curly brackets around these single-token sub/superscripts, nor should the \left / \right present in this example. With properly added whitespaces this equation becomes quite legible.
For more complex equations people use line breaks and indentations, and/or macros.
It is a random variable in this setting, as it is a function of the randomly generated password. Given a deterministic sequence, you find the definition of its Kolmogorov complexity in textbooks/Wikipedia/etc. By saying the Kolmogorov complexity will disagree with Shannon entropy, I meant the former, which is a random variable here, does not converge to the latter, contrary to the standard asymptotic setting which probably gives people the idea of using entropy to characterize password (I don't know, don't work in security).
The point of my original post is that the asymptotics break down here, and this phenomenon is not poorly understood, at least in some other communities. It is not meant to provide an alternative that is always well-defined and useful, although as I said in the grandparent comment, there is the useful implication that you can stay safe by sticking to the asymptotic regime.
Kolmogorov complexity is only unambiguously defined asymptotically, and "asymptotics is merely a heuristic". It is also uncomputable. So, to use entropy arguments for passwords, the only correct way I could think of is to generate long and (elementwise) random passwords.
Kolmogorov complexity/entropy is more suitable for this purpose, under the implicit assumption that password crackers don't have tailored prior knowledge and are just enumerating "simple" sequences. It only agrees with Shannon entropy on long ergodic sequences. The author basically constructed an example where the two notions don't agree.
> On analysis of the file, I found that the vast majority of the records are actually related to sex, porn, and other smartphone brands. There are mentions of Tibet, Hong Kong, and other religious groups, however, mentions of the CCP and “China” are also included, too
> I think it’s pretty clear that the filter is specifically used for filtering advertisements
> Steiner is not prepared to rest on his laurels. He is currently reworking part of his dissertation for publication and plans to continue his theoretical physics work.
It definitely helps that he has a lifetime of research experience (in another field).
I was about to post the same thing. Self-organisation maps seem a classical computational model to me. If the author’s point was that computational models should be biologically plausible, there are many other examples as well. I’ve never really understood what neuroscientists are talking about…