Activation Function

An activation function is the non-linear function a neuron applies to its weighted input, which lets neural networks model complex, non-linear relationships.

What is Activation Function?

Without activation functions, any stack of layers would collapse into a single linear calculation. Common choices include ReLU, sigmoid, tanh and GELU, the last being popular in transformers.

How it works

After summing its weighted inputs, a neuron passes the result through the activation function; ReLU, for example, outputs the value if positive and zero otherwise.

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