Recent submissions

Comment · 4 years ago
Neural architecture search (NAS) is a thing! But it's almost exclusively based on meta-gradients. Again, wouldn't put my money on GAs ever outperforming gradient-based methods again.
Comment · 4 years ago
An AlexNet/ResNet-type moment may be in the cards for GAs, but I wouldn't put any money on it. They're typically only one better than brute-force. This can be good enough (and is certainly easy to implement), but if you can get a gradient for your problem -- you should use that. And nowadays, you can typically get a gradient!

Most recent advances in the fields you mentioned were driven by gradient-based optimization (e.g., drug design, routing, or chip design: https://www.nature.com/articles/s41586-021-03544-w).

Nature can't SGD through genomes but has a metric ton of time, so evolution might be near-ideal for sexual reproduction. We typically don't have billions of generations, trillions of instantiations, and complex environments to play with when optimizing functions... It's telling that the fastest-evolving biological system (our brain!) certainly doesn't employ large-scale GA; if anything, it probably approximates gradients via funky distributed rules.

EDIT: The most modern application I can think of was some stuff from OpenAI (https://openai.com/blog/evolution-strategies/). But the point here is one of computational feasibility -- if they could backprop through the same workload, they would.

Comment · 5 years ago
Several hints here are severely outdated.

For instance, never train a model in end-to-end FP16. Use mixed precision, either via native TF/PyTorch or as a freebie when using TF32 on A100s. This’ll ensure that only suitable ops are run with lower precision; no need to fiddle with anything. Also, PyTorch DDP in multi-node regimes hasn’t been slower or less efficient than Horovod in ages.

Finally, buying a local cluster of TITAN Xs is an outright weird recommendation for massive models. VRAM limitations alone make this a losing proposition.

Comment · 5 years ago
Hard disagree. V100s are a perfectly valid comparison point. They're usually what's available at scale (on AWS, in private clusters, etc.) because nobody's rolled out enough A100s at this point. If you look at any paper from OpenAI et al. (basically: not Google), you'll see performance numbers for large V100 clusters.
Comment · 6 years ago
Comment · 6 years ago
> gradient descent no longer has to be written by hand

Nobody's been writing derivatives by hand for 5+ years. All major frameworks (PyTorch, Tensorflow, MXNet, autodiff, Chainer, Theano, etc.) have decent to great automatic differentiation.

The differences and improvements are more subtle (easy parallelization/vectorization, higher-order gradients, good XLA support).

Comment · 6 years ago
Mainly because it is genuinely exhausting for any medical practitioner. That lots of patients "enjoy" googling symptoms and coming up with far-fetched self-diagnoses is a given. But couple that with the perceived intellectual superiority of (software) engineers and you get a recipe for disaster. It's the equivalent of a doctor leaning over your shoulder while you're coding and telling you to remove random keywords.
Comment · 6 years ago
For this particular problem, Mask R-CNN would have been the way to go -- it spits out instances as opposed to just deciding, for each pixel, to which class it belongs. Or an SSD (if we don't care about the mask at all).
Comment · 7 years ago
Comment · 7 years ago
Yeah, that's right. Doing too little proofreading with HN comments...
Comment · 7 years ago
Their applications are tabular data (for which MLPs have never been the method of choice) and MNIST (which I could classify at 85% with a rusty nail), so it's not super impressive.

NNs and the associated toolkit shine with structured high-dimensional data where CNNs, RNNs, or modern shenanigans like Transformer networks excel. I sincerely doubt that these networks turn out to be reducible to polynomial regression in any practically useful sense of the notion. But who knows.

Comment · 7 years ago
This represents the absolute worst kind of science journalism, completely devoid of context and domain knowledge. Virtually every definitive statement in here is wrong. Their explanation of spiking alone is a complete disaster.

Out of all the modalities, vision is easily the one we know the most about. And we do so at a fairly deep level. The discussed work seems fine but it's not the groundbreaking insight it's made out to be. Great PR work from the involved scientists (or their enterprising university marketing department).

Comment · 7 years ago
Running Windows is perfectly fine; the major libraries for GPU-accelerated autodiff and networks (CUDNN with Pytorch or Tensorflow) have great support nowadays. It's the AMD GPU that remains essentially useless, as of 2019. If you want to get into the game, I'd recommend buying a middle-of-the-road NVIDIA GPU like the RTX2060.

For toying with autodiff and basic CNNs, CPU works just fine by the way...

Comment · 8 years ago
That's not quite how the process works. These papers go through multiple (> 2) revisions. At any iteration, there's ample opportunity for updating references. This applies double given how long the Cueva/Wei work has been available (preprint & CCN'17 (?) contribution).
Comment · 8 years ago
It's certainly an interesting paper, but there's a bit of publication weirdness at play here.

In October '17, Cueva & Wei put out a(n anonymous) paper that recapitulates the core result almost exactly -- that training a recurrent neural network to perform dead reckoning/path integration gives you intermediate units whose place fields strongly resemble grid cells. Critically, this only happens when regularization is applied; Cueva/Wei used noisy inputs and DeepMind implemented 50% stochastic dropout in the intermediate linear layer. There are some superficial differences (generic RNN units vs. LSTM), but at their core these studies are virtually identical. Check it out:

https://openreview.net/forum?id=B17JTOe0-

What I don't get -- why doesn't DeepMind acknowledge this result? Sure, the Nature paper was submitted in July '17, but these things go through many revisions. Clearly, DeepMind went a bit further with the whole integrating visual CNNs/grid cells part. Nonetheless: Fig. 1 is the core result, everything from Fig. 2 onwards is nice-to-have but not essential, and I feel like Cueva/Wei got there first.

Ah, well. At least the minor controversy brings in great publicity for the Cueva/Wei paper.

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