Neural Networks
Understand the neural network, how it is formulated, and why it works.
We'll cover the following...
What is a neuron?
In the world of Neural Networks (NN), the basic building block is the neuron. NNs are nothing more than a collection of neurons organized in layers, with information passing from one layer to the other. So to understand NN, we first need to understand the neuron: the basic computing unit.
Mathematically, we have:
A neuron is simply a linear classifier with a single output.
import torch.nn as nn
neuron = nn.Linear(3,1, bias=False)
Looks familiar? In most applications, we also add a bias to shift the position of the boundary line that separates the data points. This is the infamous Perceptron.
To extend this idea, we also pass this weighted average through a non-linear function that will give us the decision boundary.
Why?
Because with non-linear functions between linear layers, we can model much more complex representations with less linear layers.
Non-linearities is a key component that makes NN very rich function approximators.
Putting it all together, we have:
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