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Joined 3 years ago
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Cake day: July 1st, 2023

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  • No, you are correct. Hinton began researching ReLUs in 2010 and his students Alex Krizhevsky and Ilya Sutskever used it to train a much deeper network (AlexNet) to win the 2012 ILSVRC. The reason AlexNet was so groundbreaking was because it brought all of the gradient optimization improvements (SGD with momentum as popularized by Schmidhuber, and dropout), better activation functions (ReLU), a deeper network (8 layers), supervised training on very large datasets (necessary to learn good general-purpose convolutional kernels), and GPU acceleration into a single approach.

    NNs, and specifically CNNs, won out because they were able to create more expressive and superior image feature representations over the hand-crafted features of competing algorithms. The proof was in the vastly better performance, it was a major jump when the performance on the ILSVRC was becoming saturated. Nobody was making nearly +10% improvements on that challenge back then, it blew everybody out of the water and made NNs and deep learning impossible to ignore.

    Edit: to accentuate the point about datasets and GPUs, the original AlexNet developers really struggled to train their model on the GPUs available at the time. The model was too big and they had to split it across two GPUs to make it work. They were some of the first researchers to train large CNNs with GPUs. Without large datasets like the ILSVRC they would not have been able to train good deep hierarchical convolutions, and without better GPUs they wouldn’t have been able to make AlexNet sufficiently large or deep. Training AlexNet on CPU only for ILSVRC was out of the question, it would have taken months of full-tilt, nonstop compute for a single training run. It was more than these two things, as detailed above, but removing those two barriers really allowed CNNs and deep learning to take off. Much of the underlying NN and optimization theory had been around for decades.


  • Before AlexNet, SVMs were the best algorithms around. LeNet was the only comparable success case for NNs back then, and it was largely seen as exclusively limited to MNIST digits because deep networks were too hard to train. People used HOG+SVM, SIFT, SURF, ORB, older Haar / Viola-Jones features, template matching, random forests, Hough Transforms, sliding windows, deformable parts models… so many techniques that were made obsolete once the first deep networks became viable.

    The problem is your schooling was correct at the time, but the march of research progress eventually saw 1) the creation of large, million-scale supervised datasets (ImageNet) and 2) larger / faster GPUs with more on-card memory.

    It was fact back in ~2010 that SVMs were superior to NNs in nearly every aspect.

    Source: started a PhD on computer vision in 2012


  • I was asleep in bed one night many years ago and heard a loud bang, startling me awake. I thought for sure somebody was trying to break in a window or something. Went out, checked the house, nothing amiss. Went outside, checked around for any signs of something being off, not a thing. I then sat in my living room for 30 minutes trying to decide if it was a dream or if it would happen again. Still, nothing. I went back to sleep.

    The next morning I made coffee and sat down at my MacBook Pro. It was an older model but I immediately noticed something was wrong. The entire laptop was elevated off the table slightly. The battery had apparently expanded in the middle of the night and with enough force ripped the bottom aluminum cover through three of the screw holes. Found the source of the noise, and immediately took it for disposal.

    I was very lucky it didn’t catch fire, although it would have quickly solved my midnight mystery.










  • I don’t have any tattoos, but if I ever got one it would be 4 small circles. Three would be filled in and one would be just an outline. It’s not much, but as a father of four pregnancies but three kids it would be a small little reminder just for me. My logic has always been if I’m going to be marked on the outside, it should reflect how I’m marked on the inside.

    Four years later it still stings. I wish you peace; I wish I could say talking about it with other people has helped, but I can’t.