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2: How the Backpropagation Algorithm Works

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    3751
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    In the last chapter we saw how neural networks can learn their weights and biases using the gradient descent algorithm. There was, however, a gap in our explanation: we didn't discuss how to compute the gradient of the cost function. That's quite a gap! In this chapter I'll explain a fast algorithm for computing such gradients, an algorithm known as backpropagation.


    2: How the Backpropagation Algorithm Works is shared under a CC BY-NC license and was authored, remixed, and/or curated by Michael Nielson.

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