Activation function

In neural networks, activation functions perform a transformation on a weighted sum of inputs plus biases to a neuron in order to compute its output. Using a biological analogy, the activation function determines the “firing rate” of a neuron in response to an input or stimulus. These functions introduce non-linearities into the neural networks enabling them to perform complex tasks such as image recognition and language processing. Without non-linear activation functions, artificial neural networks behave as simple linear regression models.

Such functions include:

  • sigmoid function
  • rectified linear unit (ReLU) function
  • hyperbolic tangent (Tanh) function

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Article information

rID: 68974
Synonyms or Alternate Spellings:
  • Activation functions

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