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Gradient descent, how neural networks learn | Deep Learning Chapter 2

3Blue1Brown · 9.7M views · 2017-10-16 · 20:33

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Overview

3Blue1Brown's second neural network chapter explains cost functions and gradient descent, showing how a network learns by minimizing error during training.

On Hacker News

HN recommends the series as a very accessible way to understand the math behind machine learning and LLMs.

Recommended by 4 HN people across 3 months · HN mentions 2017–2024

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What people said

hal9000xp · 2017-11 · Strong recommendation

I'm in the same boat. For long time, I was interested in AI but at the same time intimidated by math. I'm relatively comfortable with discrete mathematics and classical algorithms and at the same time calculus and linear algebra is completely foreign to me. Also, I do not accept way to learn ML without good understanding of core principles behind it. So math is a must. A few months ago, I stumbled upon very amazing YouTube Channel 3Blue1Brown which explains math in very accessible way and at the same time I got feeling that I finally started understanding core ideas behind linear algebra and calculus. Just recently he published 4 videos about deep neural networks: [LINK] [VIDEO] [LINK] [LINK] So my fear of ML was gone away and I'm very excited to explore whole new world for neural networks and other things like support vector machines etc

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superkuh · 2024-10 · Recommendation

> when an LLM tells us that the sun rises in the east, it's not because it truly understands astronomy or the solar system. Rather, it has seen the phrase "sun rises in the east" repeated so many times in its training data that this becomes the highest probability answer. It's less about understanding and more about pattern recognition. This is not too different from most human person's experience with basic education ( [LINK] ). Though it is obvious that humans can do more than that too. And while "voting" that may be a close-enough metaphor for the multi-layer perceptron layers, it is not what is happening in the attention layers. I suggest checking out 3blue1brown's videos on gradient descent [VIDEO] and "How might LLMs store facts" [LINK] versus how attention works [LINK]

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miklosme · 2020-05 · Recommendation

If you want an extensive answer, I recommend the neural network playlist on 3Blue1Brown: [LINK] For a quick answer, watch this segment: [VIDEO]

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Video by 3Blue1Brown, played through YouTube.

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